The Treaty on the Non-Proliferation of Nuclear Weapons , commonly known as the Non-Proliferation Treaty or NPT , is an international treaty whose objective is to prevent the spread of nuclear weapons and weapons technology, to promote cooperation in the peaceful uses of nuclear energy , and to further the goal of achieving nuclear disarmament and general and complete disarmament.
Opened for signature in 1968, the treaty entered into force in 1970. As required by the text, after twenty-five years, NPT Parties met in May 1995 and agreed to extend the treaty indefinitely.  More countries have adhered to the NPT than any other arms limitation and disarmament agreement, a testament to the treaty's significance. As of August 2016, 191 states have adhered to the treaty, though North Korea , which acceded in 1985 but never came into compliance, announced its withdrawal from the NPT in 2003, following detonation of nuclear devices in violation of core obligations.  Four UN member states have never accepted the NPT, three of which are thought to possess nuclear weapons: India , Israel , and Pakistan . In addition, South Sudan , founded in 2011, has not joined.
The treaty defines nuclear-weapon states as those that have built and tested a nuclear explosive device before 1 January 1967; these are the United States , Russia , the United Kingdom , France , and China . Four other states are known or believed to possess nuclear weapons: India , Pakistan , and North Korea have openly tested and declared that they possess nuclear weapons, while Israel is deliberately ambiguous regarding its nuclear weapons status .
The NPT is often seen to be based on a central bargain:
the NPT non-nuclear-weapon states agree never to acquire nuclear weapons and the NPT nuclear-weapon states in exchange agree to share the benefits of peaceful nuclear technology and to pursue nuclear disarmament aimed at the ultimate elimination of their nuclear arsenals. 
The treaty is reviewed every five years in meetings called Review Conferences of the Parties to the Treaty of Non-Proliferation of Nuclear Weapons. Even though the treaty was originally conceived with a limited duration of 25 years, the signing parties decided, by consensus, to unconditionally extend the treaty indefinitely during the Review Conference in New York City on 11 May 1995, culminating successful U.S. government efforts led by Ambassador Thomas Graham Jr.
At the time the NPT was proposed, there were predictions of 25–30 nuclear weapon states within 20 years. Instead, over forty years later, five states are not parties to the NPT, and they include the only four additional states believed to possess nuclear weapons.  Several additional measures have been adopted to strengthen the NPT and the broader nuclear nonproliferation regime and make it difficult for states to acquire the capability to produce nuclear weapons, including the export controls of the Nuclear Suppliers Group and the enhanced verification measures of the International Atomic Energy Agency (IAEA) Additional Protocol .
Critics argue that the NPT cannot stop the proliferation of nuclear weapons or the motivation to acquire them. They express disappointment with the limited progress on nuclear disarmament, where the five authorized nuclear weapons states still have 22,000 warheads in their combined stockpile and have shown a reluctance to disarm further. Several high-ranking officials within the United Nations have said that they can do little to stop states using nuclear reactors to produce nuclear weapons.
The NPT consists of a preamble and eleven articles. Although the concept of "pillars" is not expressed anywhere in the NPT, the treaty is nevertheless sometimes interpreted as a three-pillar system,  with an implicit balance among them:
These pillars are interrelated and mutually reinforcing. An effective nonproliferation regime whose members comply with their obligations provides an essential foundation for progress on disarmament and makes possible greater cooperation on the peaceful use of nuclear energy. With the right to access the benefits of peaceful nuclear technology comes the responsibility of nonproliferation. Progress on disarmament reinforces efforts to strengthen the nonproliferation regime and to enforce compliance with obligations, thereby also facilitating peaceful nuclear cooperation. The "pillars" concept has been questioned by some who believe that the NPT is, as its name suggests, principally about nonproliferation, and who worry that "three pillars" language misleadingly implies that the three elements have equivalent importance.
First pillar: non-proliferation
Under Article I of the NPT, nuclear-weapon states pledge not to transfer nuclear weapons or other nuclear explosive devices to any recipient or in any way assist, encourage or induce any non-nuclear-weapon state in the manufacture or acquisition of a nuclear weapon. Under Article II of the NPT, non-nuclear-weapon states pledge not to acquire or exercise control over nuclear weapons or other nuclear explosive devices and not to seek or receive assistance in the manufacture of such devices. Under Article III of the Treaty, non-nuclear-weapon states pledge to accept IAEA safeguards to verify that their nuclear activities serve only peaceful purposes.
Five states are recognized by NPT as nuclear weapon states (NWS): China (signed 1992), France (1992), the Soviet Union (1968; obligations and rights now assumed by the Russian Federation), the United Kingdom (1968), and the United States (1968). These five nations are also the five permanent members of the United Nations Security Council .
These five NWS agree not to transfer "nuclear weapons or other nuclear explosive devices" and "not in any way to assist, encourage, or induce" a non-nuclear weapon state (NNWS) to acquire nuclear weapons (Article I). NNWS parties to the NPT agree not to "receive", "manufacture", or "acquire" nuclear weapons or to "seek or receive any assistance in the manufacture of nuclear weapons" (Article II). NNWS parties also agree to accept safeguards by the International Atomic Energy Agency (IAEA) to verify that they are not diverting nuclear energy from peaceful uses to nuclear weapons or other nuclear explosive devices (Article III).
The five NWS parties have made undertakings not to use their nuclear weapons against a non-NWS party except in response to a nuclear attack, or a conventional attack in alliance with a Nuclear Weapons State. However, these undertakings have not been incorporated formally into the treaty, and the exact details have varied over time. The U.S. also had nuclear warheads targeted at North Korea, a non-NWS, from 1959 until 1991. The previous United Kingdom Secretary of State for Defence , Geoff Hoon , has also explicitly invoked the possibility of the use of the country's nuclear weapons in response to a non-conventional attack by " rogue states ". In January 2006, President Jacques Chirac of France indicated that an incident of state-sponsored terrorism on France could trigger a small-scale nuclear retaliation aimed at destroying the "rogue state's" power centers.
Second pillar: disarmament
Under Article VI of the NPT, all Parties undertake to pursue good-faith negotiations on effective measures relating to cessation of the nuclear arms race, to nuclear disarmament, and to general and complete disarmament.
Article VI of the NPT represents the only binding commitment in a multilateral treaty to the goal of disarmament by the nuclear-weapon states. The NPT's preamble contains language affirming the desire of treaty signatories to ease international tension and strengthen international trust so as to create someday the conditions for a halt to the production of nuclear weapons, and treaty on general and complete disarmament that liquidates, in particular, nuclear weapons and their delivery vehicles from national arsenals.
The wording of the NPT's Article VI arguably imposes only a vague obligation on all NPT signatories to move in the general direction of nuclear and total disarmament, saying, "Each of the Parties to the Treaty undertakes to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament." Under this interpretation, Article VI does not strictly require all signatories to actually conclude a disarmament treaty. Rather, it only requires them "to negotiate in good faith."
On the other hand, some governments, especially non-nuclear-weapon states belonging to the Non-Aligned Movement , have interpreted Article VI's language as being anything but vague. In their view, Article VI constitutes a formal and specific obligation on the NPT-recognized nuclear-weapon states to disarm themselves of nuclear weapons, and argue that these states have failed to meet their obligation. The International Court of Justice (ICJ), in its advisory opinion on the Legality of the Threat or Use of Nuclear Weapons , issued 8 July 1996, unanimously interprets the text of Article VI as implying that
"There exists an obligation to pursue in good faith and bring to a conclusion negotiations leading to nuclear disarmament in all its aspects under strict and effective international control."
The ICJ opinion notes that this obligation involves all NPT parties (not just the nuclear weapon states) and does not suggest a specific time frame for nuclear disarmament. 
Critics of the NPT-recognized nuclear-weapon states (the United States, Russia, China, France, and the United Kingdom) sometimes argue that what they view as the failure of the NPT-recognized nuclear weapon states to disarm themselves of nuclear weapons, especially in the post– Cold War era, has angered some non-nuclear-weapon NPT signatories of the NPT. Such failure, these critics add, provides justification for the non-nuclear-weapon signatories to quit the NPT and develop their own nuclear arsenals.
Other observers have suggested that the linkage between proliferation and disarmament may also work the other way, i.e., that the failure to resolve proliferation threats in Iran and North Korea, for instance, will cripple the prospects for disarmament. No current nuclear weapons state, the argument goes, would seriously consider eliminating its last nuclear weapons without high confidence that other countries would not acquire them. Some observers have even suggested that the very progress of disarmament by the superpowers—which has led to the elimination of thousands of weapons and delivery systems—could eventually make the possession of nuclear weapons more attractive by increasing the perceived strategic value of a small arsenal. As one U.S. official and NPT expert warned in 2007, "logic suggests that as the number of nuclear weapons decreases, the 'marginal utility' of a nuclear weapon as an instrument of military power increases. At the extreme, which it is precisely disarmament's hope to create, the strategic utility of even one or two nuclear weapons would be huge." 
Third pillar: peaceful use of nuclear energy
NPT Article IV acknowledges the right of all Parties to develop nuclear energy for peaceful purposes and to benefit from international cooperation in this area, in conformity with their nonproliferation obligations. Article IV also encourages such cooperation.
The third pillar allows for and agrees upon the transfer of nuclear technology and materials to NPT signatory countries for the development of civilian nuclear energy programs in those countries, as long as they can demonstrate that their nuclear programs are not being used for the development of nuclear weapons. 
Since very few of the states with nuclear energy programs are willing to abandon the use of nuclear energy, the third pillar of the NPT under Article IV provides other states with the possibility to do the same, but under conditions intended to make it difficult to develop nuclear weapons.
The treaty recognizes the inalienable right of sovereign states to use nuclear energy for peaceful purposes, but restricts this right for NPT parties to be exercised "in conformity with Articles I and II" (the basic nonproliferation obligations that constitute the "first pillar" of the treaty). As the commercially popular light water reactor nuclear power station uses enriched uranium fuel, it follows that states must be able either to enrich uranium or purchase it on an international market. Mohamed ElBaradei , then Director General of the International Atomic Energy Agency , has called the spread of enrichment and reprocessing capabilities the " Achilles' heel " of the nuclear nonproliferation regime. As of 2007 13 states have an enrichment capability. 
Because the availability of fissile material has long been considered the principal obstacle to, and "pacing element" for, a country's nuclear weapons development effort, it was declared a major emphasis of U.S. policy in 2004 to prevent the further spread of uranium enrichment and plutonium reprocessing (a.k.a. "ENR") technology. Countries possessing ENR capabilities, it is feared, have what is in effect the option of using this capability to produce fissile material for weapons use on demand, thus giving them what has been termed a "virtual" nuclear weapons program.  The degree to which NPT members have a "right" to ENR technology notwithstanding its potentially grave proliferation implications, therefore, is at the cutting edge of policy and legal debates surrounding the meaning of Article IV and its relation to Articles I, II, and III of the treaty.
Countries that have signed the treaty as Non-Nuclear Weapons States and maintained that status have an unbroken record of not building nuclear weapons. However, Iraq was cited by the IAEA with punitive sanctions enacted against it by the UN Security Council for violating its NPT safeguards obligations; North Korea never came into compliance with its NPT safeguards agreement and was cited repeatedly for these violations,  and later withdrew from the NPT and tested multiple nuclear devices; Iran was found in non-compliance with its NPT safeguards obligations in an unusual non-consensus decision because it "failed in a number of instances over an extended period of time" to report aspects of its enrichment program;   and Libya pursued a clandestine nuclear weapons program before abandoning it in December 2003.
In 1991, Romania reported previously undeclared nuclear activities by the former regime and the IAEA reported this non-compliance to the Security Council for information only. In some regions, the fact that all neighbors are verifiably free of nuclear weapons reduces any pressure individual states might feel to build those weapons themselves, even if neighbors are known to have peaceful nuclear energy programs that might otherwise be suspicious. In this, the treaty works as designed.
Article I :  Each nuclear-weapons state (NWS) undertakes not to transfer, to any recipient, nuclear weapons, or other nuclear explosive devices, and not to assist any non-nuclear weapon state to manufacture or acquire such weapons or devices.
Article II : Each non-NWS party undertakes not to receive, from any source, nuclear weapons, or other nuclear explosive devices; not to manufacture or acquire such weapons or devices; and not to receive any assistance in their manufacture.
Article III : Each non-NWS party undertakes to conclude an agreement with the IAEA for the application of its safeguards to all nuclear material in all of the state's peaceful nuclear activities and to prevent diversion of such material to nuclear weapons or other nuclear explosive devices.
Article IV : 1. Nothing in this Treaty shall be interpreted as affecting the inalienable right of all the Parties to the Treaty to develop research, production and use of nuclear energy for peaceful purposes without discrimination and in conformity with Articles I and II of this Treaty.
2. All the Parties to the Treaty undertake to facilitate, and have the right to participate in, the fullest possible exchange of equipment, materials and scientific and technological information for the peaceful uses of nuclear energy. Parties to the Treaty in a position to do so shall also co-operate in contributing alone or together with other States or international organizations to the further development of the applications of nuclear energy for peaceful purposes, especially in the territories of non-nuclear-weapon States Party to the Treaty, with due consideration for the needs of the developing areas of the world.
Article VI : Each party "undertakes to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a Treaty on general and complete disarmament under strict and effective international control".
Article IX : "For the purposes of this Treaty, a nuclear-weapon State is one which has manufactured and exploded a nuclear weapon or other nuclear explosive device prior to 1 January 1967."
Article X : Establishes the right to withdraw from the Treaty giving 3 months' notice. It also establishes the duration of the Treaty (25 years before 1995 Extension Initiative).
The impetus behind the NPT was concern for the safety of a world with many nuclear weapon states. It was recognized that the cold war deterrent relationship between just the United States and Soviet Union was fragile. Having more nuclear-weapon states would reduce security for all, multiplying the risks of miscalculation, accidents, unauthorized use of weapons, or from escalation in tensions, nuclear conflict. Moreover, the use of nuclear weapons in Hiroshima and Nagasaki in 1945, it has been apparent that the development of nuclear capabilities by States could enable them to divert technology and materials for weapons purposes. Thus, the problem of preventing such diversions became a central issue in discussions on peaceful uses of nuclear energy.
Initial efforts, which began in 1946, to create an international system enabling all States to have access to nuclear technology under appropriate safeguards, were terminated in 1949 without the achievement of this objective, due to serious political differences between the major Powers. By then, both the United States and the former Soviet Union had tested nuclear weapons, and were beginning to build their stockpiles.
In December 1953, US President Dwight D. Eisenhower in his " Atoms for Peace " proposal, presented to the eighth session of the United Nations General Assembly, urged that an international organization be established to disseminate peaceful nuclear technology, while guarding against development of weapons capabilities in additional countries. His proposal resulted in 1957 in the establishment of the International Atomic Energy Agency (IAEA), which was charged with the dual responsibility of promotion and control of nuclear technology. IAEA technical activities began in 1958. An interim safeguards system for small nuclear reactors, put in place in 1961, was replaced in 1964 by a system covering larger installations and, over the following years, was expanded to include additional nuclear facilities. In recent years, efforts to strengthen the effectiveness and improve the efficiency of the IAEA safeguards system culminated in the approval of the Model Additional Protocol by the IAEA Board of Governors in May 1997.
Within the framework of the United Nations, the principle of nuclear non-proliferation was addressed in negotiations as early as 1957. The NPT process was launched by Frank Aiken , Irish Minister for External Affairs, in 1958. The NPT gained significant momentum in the early 1960s. The structure of a treaty to uphold nuclear non-proliferation as a norm of international behaviour had become clear by the mid-1960s, and by 1968 final agreement had been reached on a Treaty that would prevent the proliferation of nuclear weapons, enable cooperation for the peaceful use of nuclear energy, and further the goal of achieving nuclear disarmament. It was opened for signature in 1968, with Finland the first State to sign . Accession became nearly universal after the end of the Cold War and of South African apartheid . In 1992, China and France acceded to the NPT, the last of the five nuclear powers recognized by the treaty to do so.
The Treaty provided, in article X, for a conference to be convened 25 years after its entry into force to decided whether the Treaty should continue in force indefinitely, or be extended for an additional fixed period of periods. Accordingly, at the NPT Review and Extension Conference in May 1995, States parties to the Treaty agreed-without a vote-on the Treaty's indefinited extension, and decided that review conferences should continue to be held every five years. After Brazil acceded to the NPT in 1998, the only remaining non-nuclear-weapons state which had not signed was Cuba, which joined NPT (and the Treaty of Tlatelolco NWFZ ) in 2002.
Several NPT signatories have given up nuclear weapons or nuclear weapons programs. South Africa undertook a nuclear weapons program, but has since renounced it and signed the treaty in 1991 after destroying its small nuclear arsenal ; after this, the remaining African countries signed the treaty. The former Soviet Republics where nuclear weapons had been based, namely Ukraine, Belarus and Kazakhstan, transferred those weapons to Russia and joined NPT by 1994 following the signature of the Budapest Memorandum on Security Assurances .
Successor states from the breakups of Yugoslavia and Czechoslovakia also joined the treaty soon after their independence. Montenegro and East Timor were the last countries to sign the treaty on their independence in 2006 and 2003; the only other country to sign in the 21st century was Cuba in 2002. The three Micronesian countries in Compact of Free Association with the USA joined NPT in 1995, along with Vanuatu.
Major South American countries Argentina, Chile, and Brazil joined in 1995 and 1998. Arabian Peninsula countries included Saudi Arabia and Bahrain in 1988, Qatar and Kuwait in 1989, UAE in 1995, and Oman in 1997. The tiny European states of Monaco and Andorra joined in 1995-6. Also signing in the 1990s were Myanmar in 1992 and Guyana in 1993.
United States–NATO nuclear weapons sharing
At the time the treaty was being negotiated, NATO had in place secret nuclear weapons sharing agreements whereby the United States provided nuclear weapons to be deployed by, and stored in, other NATO states. Some argue this is an act of proliferation violating Articles I and II of the treaty. A counter-argument is that the U.S. controlled the weapons in storage within the NATO states, and that no transfer of the weapons or control over them was intended "unless and until a decision were made to go to war, at which the treaty would no longer be controlling", so there is no breach of the NPT.  These agreements were disclosed to a few of the states, including the Soviet Union , negotiating the treaty, but most of the states that signed the NPT in 1968 would not have known about these agreements and interpretations at that time. 
As of 2005, it is estimated that the United States still provides about 180 tactical B61 nuclear bombs for use by Belgium, Germany, Italy, the Netherlands and Turkey under these NATO agreements.  Many states, and the Non-Aligned Movement , now argue this violates Articles I and II of the treaty, and are applying diplomatic pressure to terminate these agreements. They point out that the pilots and other staff of the "non-nuclear" NATO states practice handling and delivering the U.S. nuclear bombs, and non-U.S. warplanes have been adapted to deliver U.S. nuclear bombs which must have involved the transfer of some technical nuclear weapons information. NATO believes its "nuclear forces continue to play an essential role in war prevention, but their role is now more fundamentally political". 
U.S. nuclear sharing policies were originally designed to help prevent the proliferation of nuclear weapons—not least by persuading the then West Germany not to develop an independent nuclear capability by assuring it that West Germany would be able, in the event of war with the Warsaw Pact, to wield (U.S.) nuclear weapons in self-defense. (Until that point of all-out war, however, the weapons themselves would remain in U.S. hands.) The point was to limit the spread of countries having their own nuclear weapons programs, helping ensure that NATO allies would not choose to go down the proliferation route.  (West Germany was discussed in U.S. intelligence estimates for a number of years as being a country with the potential to develop nuclear weapons capabilities of its own if officials in Bonn were not convinced that their defense against the Soviet Union and its allies could otherwise be met.  )
Four states—India, Israel, Pakistan, and South Sudan—have never signed the treaty. India and Pakistan have publicly disclosed their nuclear weapon programs, and Israel has a long-standing policy of deliberate ambiguity with regards to its nuclear program (see List of states with nuclear weapons ).
India has detonated nuclear devices, first in 1974 and again in 1998.  India is estimated to have enough fissile material for more than 150 warheads.  India was among the few countries to have a no first use policy, a pledge not to use nuclear weapons unless first attacked by an adversary using nuclear weapons, however India's former NSA Shivshankar Menon signaled a significant shift from "no first use" to "no first use against non-nuclear weapon states" in a speech on the occasion of Golden Jubilee celebrations of the National Defence College in New Delhi on 21 October 2010, a doctrine Menon said reflected India's "strategic culture, with its emphasis on minimal deterrence".  
India argues that the NPT creates a club of "nuclear haves" and a larger group of "nuclear have-nots" by restricting the legal possession of nuclear weapons to those states that tested them before 1967, but the treaty never explains on what ethical grounds such a distinction is valid. India's then External Affairs Minister Pranab Mukherjee said during a visit to Tokyo in 2007: "If India did not sign the NPT, it is not because of its lack of commitment for non-proliferation, but because we consider NPT as a flawed treaty and it did not recognize the need for universal, non-discriminatory verification and treatment."  Although there have been unofficial discussions on creating a South Asian nuclear weapons free zone, including India and Pakistan, this is considered to be highly unlikely for the foreseeable future. 
In early March 2006, India and the United States finalized an agreement, in the face of criticism in both countries, to restart cooperation on civilian nuclear technology. Under the deal India has committed to classify 14 of its 22 nuclear power plants as being for civilian use and to place them under IAEA safeguards. Mohamed ElBaradei , then Director General of the IAEA, welcomed the deal by calling India "an important partner in the non-proliferation regime." 
In December 2006, United States Congress approved the United States-India Peaceful Atomic Energy Cooperation Act , endorsing a deal that was forged during Prime Minister Singh's visit to the United States in July 2005 and cemented during President Bush's visit to India earlier in 2006. The legislation allows for the transfer of civilian nuclear material to India. Despite its status outside the Nuclear Non-Proliferation Treaty, nuclear cooperation with India was permitted on the basis of its clean non-proliferation record, and India's need for energy fueled by its rapid industrialization and a billion-plus population. 
On 1 August 2008, the IAEA approved the India Safeguards Agreement  and on 6 September 2008, India was granted the waiver at the Nuclear Suppliers Group (NSG) meeting held in Vienna, Austria. The consensus was arrived after overcoming misgivings expressed by Austria, Ireland and New Zealand and is an unprecedented step in giving exemption to a country, which has not signed the NPT and the Comprehensive Test Ban Treaty (CTBT).   While India could commence nuclear trade with other willing countries.  The U.S. Congress approved this agreement and President Bush signed it on 8 October 2008. 
When China announced expanded nuclear cooperation with Pakistan in 2010, proponents of arms control denounced both the deals, claiming that they weakened the NPT by facilitating nuclear programmes in states which are not parties to the NPT. 
As of January 2011, Australia, a top three producer and home to worlds largest known reserves , had continued its refusal to export Uranium to India despite diplomatic pressure from India.  In November 2011 the Australian Prime Minister announced a desire to allow exports to India,  a policy change which was authorized by her party's national conference in December.  On 4 December 2011, Prime Minister Julia Gillard overturned Australia's long-standing ban on exporting uranium to India.  She further said "We should take a decision in the national interest, a decision about strengthening our strategic partnership with India in this the Asian century," and said that any agreement to sell uranium to India would include strict safeguards to ensure it would only be used for civilian purposes, and not end up in nuclear weapons.  On Sep 5, 2014; Australian Prime Minister Tony Abbott sealed a civil nuclear deal to sell uranium to India. "We signed a nuclear cooperation agreement because Australia trusts India to do the right thing in this area, as it has been doing in other areas," Abbott told reporters after he and Indian Prime Minister Narendra Modi signed a pact to sell uranium for peaceful power generation. 
In May 1998, following India's nuclear tests earlier that month, Pakistan conducted two sets of nuclear tests, the Chagai-I and Chagai-II . Although there is little confirmed information in public, as of 2015, Pakistan was estimated to have as many as 120 warheads.   According to analyses of the Carnegie Endowment for International Peace and the Stimson Center , Pakistan has enough fissile material for 350 warheads. 
Pakistani officials argue that the NPT is discriminatory. When asked at a briefing in 2015 whether Islamabad would sign the NPT if Washington requested it, Foreign Secretary Aizaz Ahmad Chaudhry was quoted as responding "It is a discriminatory treaty. Pakistan has the right to defend itself, so Pakistan will not sign the NPT. Why should we?"  Until 2010, Pakistan had always maintained the position that it would sign the NPT if India did so. In 2010, Pakistan abandoned this historic position and stated that it would join the NPT only as a recognized nuclear-weapon state. 
The NSG Guidelines currently rule out nuclear exports by all major suppliers to Pakistan, with very narrow exceptions, since it does not have full-scope IAEA safeguards (i.e. safeguards on all its nuclear activities). Pakistan has sought to reach an agreement similar to that with India,  but these efforts have been rebuffed by the United States and other NSG members, on the grounds that Pakistan's track record as a nuclear proliferator makes it impossible for it to have any sort of nuclear deal in the near future.
By 2010, China reportedly signed a civil nuclear agreement with Pakistan, using the justification that the deal was "peaceful."  The British government criticized this, on the grounds that 'the time is not yet right for a civil nuclear deal with Pakistan'.  China did not seek formal approval from the nuclear suppliers group , and claimed instead that its cooperation with Pakistan was "grandfathered" when China joined the NSG, a claim that was disputed by other NSG members.  Pakistan applied for membership on May 19, 2016,  supported by Turkey and China.   However, many NSG members opposed Pakistan's membership bid due to its track record, including the illicit procurement network of Pakistani scientist A.Q. Khan, which aided the nuclear programs of Iran, Libya and North Korea.   Pakistani officials reiterated the request in August 2016. 
Israel has a long-standing policy of deliberate ambiguity with regards to its nuclear program (see List of countries with nuclear weapons ). Israel has been developing nuclear technology at its Dimona site in the Negev since 1958, and some nonproliferation analysts estimate that Israel may have stockpiled between 100 and 200 warheads using reprocessed plutonium. The position on the NPT is explained in terms of "Israeli exceptionality", a term coined by Professor Gerald M. Steinberg , in reference to the perception that the country's small size, overall vulnerability, as well as the history of deep hostility and large-scale attacks by neighboring states, require a deterrent capability. 
The Israeli government refuses to confirm or deny possession of nuclear weapons, although this is now regarded as an open secret after Israeli low level nuclear technician Mordechai Vanunu —subsequently arrested and sentenced for treason by Israel—published evidence about the program to the British Sunday Times in 1986.
On 18 September 2009 the General Conference of the International Atomic Energy Agency called on Israel to open its nuclear facilities to IAEA inspection and adhere to the non-proliferation treaty as part of a resolution on "Israeli nuclear capabilities," which passed by a narrow margin of 49–45 with 16 abstentions. The chief Israeli delegate stated that "Israel will not co-operate in any matter with this resolution."  However, similar resolutions were defeated in 2010, 2013 and 2014. As with Pakistan, the NSG Guidelines currently rule out nuclear exports by all major suppliers to Israel.
North Korea ratified the treaty on 12 December 1985, but gave notice of withdrawal from the treaty on 10 January 2003 following U.S. allegations that it had started an illegal enriched uranium weapons program, and the U.S. subsequently stopping fuel oil shipments under the Agreed Framework  which had resolved plutonium weapons issues in 1994.  The withdrawal became effective 10 April 2003 making North Korea the first state ever to withdraw from the treaty.  North Korea had once before announced withdrawal, on 12 March 1993, but suspended that notice before it came into effect. 
On 10 February 2005, North Korea publicly declared that it possessed nuclear weapons and pulled out of the six-party talks hosted by China to find a diplomatic solution to the issue. "We had already taken the resolute action of pulling out of the Nuclear Non-Proliferation Treaty and have manufactured nuclear arms for self-defence to cope with the Bush administration's evermore undisguised policy to isolate and stifle the DPRK [Democratic People's Republic of Korea]," a North Korean Foreign Ministry statement said regarding the issue.  Six-party talks resumed in July 2005.
On 19 September 2005, North Korea announced that it would agree to a preliminary accord. Under the accord, North Korea would scrap all of its existing nuclear weapons and nuclear production facilities, rejoin the NPT, and readmit IAEA inspectors. The difficult issue of the supply of light water reactors to replace North Korea's indigenous nuclear power plant program , as per the 1994 Agreed Framework , was left to be resolved in future discussions. On the next day North Korea reiterated its known view that until it is supplied with a light water reactor it will not dismantle its nuclear arsenal or rejoin the NPT. 
On 2 October 2006, the North Korean foreign minister announced that his country was planning to conduct a nuclear test "in the future", although it did not state when.  On Monday, 9 October 2006 at 01:35:28 (UTC) the United States Geological Survey detected a magnitude 4.3 seismic event 70 km (43 mi) north of Kimchaek, North Korea indicating a nuclear test.  The North Korean government announced shortly afterward that they had completed a successful underground test of a nuclear fission device.
In 2007, reports from Washington suggested that the 2002 CIA reports stating that North Korea was developing an enriched uranium weapons program, which led to North Korea leaving the NPT, had overstated or misread the intelligence.     On the other hand, even apart from these press allegations—which some critics worry could have been planted in order to justify the United States giving up trying to verify the dismantlement of Pyongyang's uranium program in the face of North Korean intransigence—there remains some information in the public record indicating the existence of a uranium effort. Quite apart from the fact that North Korean First Vice Minister Kang Sok Ju at one point admitted the existence of a uranium enrichment program, Pakistan's then-President Musharraf revealed that the A.Q. Khan proliferation network had provided North Korea with a number of gas centrifuges designed for uranium enrichment. Additionally, press reports have cited U.S. officials to the effect that evidence obtained in dismantling Libya's WMD programs points toward North Korea as the source for Libya's uranium hexafluoride (UF 6 ) – which, if true, would mean that North Korea has a uranium conversion facility for producing feedstock for centrifuge enrichment. 
Iran is a party to the NPT but was found in non-compliance with its NPT safeguards agreement, and the status of its nuclear program remains in dispute. In November 2003 IAEA Director General Mohamed ElBaradei reported that Iran had repeatedly and over an extended period failed to meet its safeguards obligations, including by failing to declare its uranium enrichment program.  After about two years of EU3-led diplomatic efforts and Iran temporarily suspending its enrichment program,  the IAEA Board of Governors, acting under Article XII.C of the IAEA Statute, found in a rare non-consensus decision with 12 abstentions that these failures constituted non-compliance with the IAEA safeguards agreement.  This was reported to the UN Security Council in 2006,  after which the Security Council passed a resolution demanding that Iran suspend its enrichment.  Instead, Iran resumed its enrichment program. 
The IAEA has been able to verify the non-diversion of declared nuclear material in Iran, and is continuing its work on verifying the absence of undeclared activities.  In February 2008, the IAEA also reported that it was working to address "alleged studies" of weaponization, based on documents provided by certain Member States, which those states claimed originated from Iran. Iran rejected the allegations as "baseless" and the documents as "fabrications."  In June 2009, the IAEA reported that Iran had not "cooperated with the Agency in connection with the remaining issues ... which need to be clarified to exclude the possibility of military dimensions to Iran's nuclear program." 
The United States concluded that Iran violated its Article III NPT safeguards obligations, and further argued based on circumstantial evidence that Iran's enrichment program was for weapons purposes and therefore violated Iran's Article II nonproliferation obligations.  The November 2007 US National Intelligence Estimate (NIE) later concluded that Iran had halted an active nuclear weapons program in the fall of 2003 and that it had remained halted as of mid-2007. The NIE's "Key Judgments," however, also made clear that what Iran had actually stopped in 2003 was only "nuclear weapon design and weaponization work and covert uranium conversion-related and uranium enrichment-related work"-namely, those aspects of Iran's nuclear weapons effort that had not by that point already been leaked to the press and become the subject of IAEA investigations. 
Since Iran's uranium enrichment program at Natanz—and its continuing work on a heavy water reactor at Arak that would be ideal for plutonium production—began secretly years before in conjunction with the very weaponization work the NIE discussed and for the purpose of developing nuclear weapons, many observers find Iran's continued development of fissile material production capabilities distinctly worrying. Particularly because fissile material availability has long been understood to be the principal obstacle to nuclear weapons development and the primary "pacing element" for a weapons program, the fact that Iran has reportedly suspended weaponization work may not mean very much.  As U.S. Director of National Intelligence Mike McConnell has put it, the aspects of its work that Iran allegedly suspended were thus "probably the least significant part of the program." 
Iran states it has a legal right to enrich uranium for peaceful purposes under the NPT, and further says that it "has constantly complied with its obligations under the NPT and the Statute of the International Atomic Energy Agency".  Iran also states that its enrichment program is part of its civilian nuclear energy program, which is allowed under Article IV of the NPT. The Non-Aligned Movement has welcomed the continuing cooperation of Iran with the IAEA and reaffirmed Iran's right to the peaceful uses of nuclear technology.  UN Secretary General Ban Ki-moon has welcomed the continued dialogue between Iran and the IAEA, and has called for a peaceful resolution to the issue. 
In April 2010, during the signing of the U.S.-Russia New START Treaty, President Obama said that the United States, Russia, and other nations are demanding that Iran face consequences for failing to fulfill their obligations under the Nuclear Non-Proliferation Treaty, and that "we will not tolerate actions that flout the NPT, risk an arms race in a vital region, and threaten the credibility of the international community and our collective security." 
South Africa is the only country that developed nuclear weapons by itself and later dismantled them – unlike the former Soviet states Ukraine, Belarus and Kazakhstan, which inherited nuclear weapons from the former USSR and also acceded to the NPT as non-nuclear weapon states.
During the days of apartheid , the South African government developed a deep fear of both a black uprising and the threat of communism. This led to the development of a secret nuclear weapons program as an ultimate deterrent. South Africa has a large supply of uranium, which is mined in the country's gold mines. The government built a nuclear research facility at Pelindaba near Pretoria where uranium was enriched to fuel grade for the Koeberg Nuclear Power Station as well as weapon grade for bomb production.
In 1991, after international pressure and when a change of government was imminent, South African Ambassador to the United States Harry Schwarz signed the Nuclear Non-Proliferation Treaty. In 1993, the then president Frederik Willem de Klerk openly admitted that the country had developed a limited nuclear weapon capability. These weapons were subsequently dismantled before South Africa acceded to the NPT and opened itself up to IAEA inspection. In 1994, the IAEA completed its work and declared that the country had fully dismantled its nuclear weapons program.
Libya had signed and ratified the Nuclear Non-Proliferation Treaty and was subject to IAEA nuclear safeguards inspections, but undertook a secret nuclear weapons development program in violation of its NPT obligations, using material and technology provided by the A.Q. Khan proliferation network—including actual nuclear weapons designs allegedly originating in China. Libya began secret negotiations with the United States and the United Kingdom in March 2003 over potentially eliminating its WMD programs . In October 2003, Libya was embarrassed by the interdiction of a shipment of Pakistani-designed centrifuge parts sent from Malaysia, also as part of A. Q. Khan's proliferation ring.
In December 2003, Libya announced that it had agreed to eliminate all its WMD programs, and permitted U.S. and British teams (as well as IAEA inspectors) into the country to assist this process and verify its completion. The nuclear weapons designs, gas centrifuges for uranium enrichment, and other equipment—including prototypes for improved SCUD ballistic missiles —were removed from Libya by the United States. (Libyan chemical weapons stocks and chemical bombs were also destroyed on site with international verification, with Libya joining the Chemical Weapons Convention.) Libya's non-compliance with its IAEA safeguards was reported to the U.N. Security Council, but with no action taken, as Libya's return to compliance with safeguards and Article II of the NPT was welcomed.
In 2011 the Libyan government was overthrown in the Libyan Civil War with the assistance of a military intervention by NATO forces acting under the auspices of United Nations Security Council Resolution 1973 . It was speculated in the media (especially in the Middle Eastern media) that NATO's intervention in Libya shortly after the nation agreed to nuclear and chemical weapons disarmament would make other countries such as North Korea more reluctant to give up nuclear programs due to the risk of being weakened as a result.
Syria is a signatory to the NPT and has a limited civil nuclear program. Before the advent of the Syrian Civil War it was known to operate only one small Chinese-built research reactor, SRR-1. Despite being a proponent of a Weapons of Mass Destruction Free Zone in the Middle East the country was accused of pursuing a military nuclear program with a reported nuclear facility in a desert Syrian region of Deir ez-Zor. The reactor's components had likely been designed and manufactured in North Korea, with the reactor's striking similarity in shape and size to the North Korean Yongbyon Nuclear Scientific Research Center. That information alarmed Israeli military and intelligence to such a degree that the idea of a targeted airstrike was conceived. It resulted in Operation Orchard , that took place on September 6, 2007 and saw as many as eight Israeli aircraft taking part. Israeli government is said to have bounced the idea of the operation off the US Bush administration, although the latter disagreed to participate. The nuclear reactor was destroyed in the attack, which also killed about ten North Korean workers. The attack didn't cause an international outcry or any serious Syrian retaliatory moves as both parties tried to keep it secret: Israel didn't want publicity as regards its breach of international law while Syria wasn't willing to acknowledge its clandestine nuclear program.
Leaving the treaty
Article X allows a state to leave the treaty if "extraordinary events, related to the subject matter of this Treaty, have jeopardized the supreme interests of its country", giving three months' (ninety days') notice. The state is required to give reasons for leaving the NPT in this notice.
NATO states argue that when there is a state of "general war" the treaty no longer applies, effectively allowing the states involved to leave the treaty with no notice. This is a necessary argument to support the NATO nuclear weapons sharing policy, but a troubling one for the logic of the treaty. NATO's argument is based on the phrase "the consequent need to make every effort to avert the danger of such a war" in the treaty preamble, inserted at the behest of U.S. diplomats, arguing that the treaty would at that point have failed to fulfill its function of prohibiting a general war and thus no longer be binding.  Many states do not accept this argument. See United States–NATO nuclear weapons sharing above.
North Korea has also caused an uproar by its use of this provision of the treaty. Article X.1 only requires a state to give three months' notice in total, and does not provide for other states to question a state's interpretation of "supreme interests of its country". In 1993, North Korea gave notice to withdraw from the NPT. However, after 89 days, North Korea reached agreement with the United States to freeze its nuclear program under the Agreed Framework and "suspended" its withdrawal notice. In October 2002, the United States accused North Korea of violating the Agreed Framework by pursuing a secret uranium enrichment program, and suspended shipments of heavy fuel oil under that agreement. In response, North Korea expelled IAEA inspectors, disabled IAEA equipment, and, on 10 January 2003, announced that it was ending the suspension of its previous NPT withdrawal notification. North Korea said that only one more day's notice was sufficient for withdrawal from the NPT, as it had given 89 days before.
The IAEA Board of Governors rejected this interpretation. Most countries held that a new three-months withdrawal notice was required, and some questioned whether North Korea's notification met the "extraordinary events" and "supreme interests" requirements of the treaty. The Joint Statement of 19 September 2005 at the end of the Fourth Round of the Six-Party Talks called for North Korea to "return" to the NPT, implicitly acknowledging that it had withdrawn.
Recent and coming events
The main outcome of the 2000 Conference was the adoption by consensus of a comprehensive Final Document, which included among other things "practical steps for the systematic and progressive efforts" to implement the disarmament provisions of the NPT, commonly referred to as the Thirteen Steps .
On 18 July 2005, US President George W. Bush met Indian Prime Minister Manmohan Singh and declared that he would work to change US law and international rules to permit trade in US civilian nuclear technology with India. Some, such as British columnist George Monbiot , argue that the U.S.-India nuclear deal, in combination with US attempts to deny Iran (an NPT signatory) civilian nuclear fuel-making technology, may destroy the NPT regime, while others contend that such a move will likely bring India, an NPT non-signatory, under closer international scrutiny.
In the first half of 2010, it was strongly believed that China had signed a civilian nuclear deal with Pakistan claiming that the deal was "peaceful". 
Arms control advocates criticised the reported China-Pakistan deal as they did in case of U.S.-India deal claiming that both the deals violate the NPT by facilitating nuclear programmes in states which are not parties to the NPT.  Some reports asserted that the deal was a strategic move by China to balance US influence in South-Asia . 
According to a report published by U.S. Department of Defense in 2001, China had provided Pakistan with nuclear materials and has given critical technological assistance in the construction of Pakistan's nuclear weapons development facilities, in violation of the Nuclear Non-Proliferation Treaty, of which China even then was a signatory.  
At the , there were stark differences between the United States, which wanted the conference to focus on non-proliferation, especially on its allegations against Iran, and most other countries, who emphasized the lack of serious nuclear disarmament by the nuclear powers. The non-aligned countries reiterated their position emphasizing the need for nuclear disarmament.
The 2010 Review Conference was held in May 2010 in New York City, and adopted a final document that included a summary by the Review Conference President, Ambassador Libran Capactulan of the Philippines, and an Action Plan that was adopted by consensus. The 2010 conference was generally considered a success because it reached consensus where the previous Review Conference in 2005 ended in disarray, a fact that many attributed to the U.S. President Barack Obama 's commitment to nuclear nonproliferation and disarmament. Some have warned that this success raised unrealistically high expectations that could lead to failure at the next Review Conference in 2015.
The " Global Summit on Nuclear Security " took place 12–13 April 2010. The summit was proposed by President Obama in Prague and was intended to strengthen the Nuclear Non-Proliferation Treaty in conjunction with the Proliferation Security Initiative and the Global Initiative to Combat Nuclear Terrorism . Forty seven states and three international organizations took part in the summit, which issued a communiqué and a work plan. For further information see 2010 Nuclear Security Summit .
In a major policy speech at the Brandenburg Gate in Berlin on 19 June 2013, United States President Barack Obama outlined plans to further reduce the number of warheads in the U.S. nuclear arsenal .  According to Foreign Policy , Obama proposed a "one-third reduction in strategic nuclear warheads - on top of the cuts already required by the New START treaty - bringing the number of deployed warheads to about 1,000."  Obama is seeking to "negotiate these reductions with Russia to continue to move beyond Cold War nuclear postures," according to briefing documents provided to Foreign Policy .  In the same speech, Obama emphasized his administration's efforts to isolate any nuclear weapons capabilities emanating from Iran and North Korea . He also called for a renewed bipartisan effort in the United States Congress to ratify the Comprehensive Nuclear-Test-Ban Treaty and called on countries to negotiate a new treaty to end the production of fissile material for nuclear weapons .
On 24 April 2014, it was announced that the nation of the Marshall Islands has brought suit in The Hague against the United States, the former Soviet Union, the United Kingdom, France, China, India, Pakistan, North Korea and Israel seeking to have the disarmament provisions of the NNPT enforced.
The 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) was held at the United Nations in New York from 27 April to 22 May 2015 and presided over by Ambassador Taous Feroukhi of Algeria. The Treaty, particularly article VIII, paragraph 3, envisages a review of the operation of the Treaty every five years, a provision which was reaffirmed by the States parties at the 1995 NPT Review and Extension Conference and the 2000 NPT Review Conference. At the 2015 NPT Review Conference, States parties examined the implementation of the Treaty's provisions since 2010. Despite intensive consultations, the Conference was not able to reach agreement on the substantive part of the draft Final Document.
Criticism and responses
Over the years the NPT has come to be seen by many Third World states as "a conspiracy of the nuclear 'haves' to keep the nuclear 'have-nots' in their place". This argument has roots in Article VI of the treaty which "obligates the nuclear weapons states to liquidate their nuclear stockpiles and pursue complete disarmament. The non-nuclear states see no signs of this happening".  Some argue that the NWS have not fully complied with their disarmament obligations under Article VI of the NPT. Some countries such as India have criticized the NPT, because it "discriminated against states not possessing nuclear weapons on January 1, 1967," while Iran and numerous Arab states have criticized Israel for not signing the NPT. There has been disappointment with the limited progress on nuclear disarmament, where the five authorized nuclear weapons states still have 22,000 warheads among them and have shown a reluctance to disarm further.
As noted , the International Court of Justice, in its advisory opinion on the Legality of the Threat or Use of Nuclear Weapons , stated that "there exists an obligation to pursue in good faith and bring to a conclusion negotiations leading to nuclear disarmament in all its aspects under strict and effective international control.  Such an obligation requires that states actively pursue measures to reduce the numbers of nuclear weapons and the importance of their role in military force structures. Some critics of the nuclear-weapons states contend that they have failed to comply with Article VI by failing to make disarmament the driving force in national planning and policy with respect to nuclear weapons, even while they ask other states to plan for their security without nuclear weapons.
The United States responds to criticism of its disarmament record by pointing out that since the end of the Cold War it has eliminated over 13,000 nuclear weapons and eliminated over 80% of its deployed strategic warheads and 90% of non-strategic warheads deployed to NATO, in the process eliminating whole categories of warheads and delivery systems and reducing its reliance on nuclear weapons. U.S. officials have also pointed out the ongoing U.S. work to dismantle nuclear warheads. When current accelerated dismantlement efforts ordered by President George W. Bush have been completed, the U.S. arsenal will be less than a quarter of its size at the end of the Cold War, and smaller than it has been at any point since the Eisenhower administration, well before the drafting of the NPT.
The United States has also purchased many thousands of weapons' worth of uranium formerly in Soviet nuclear weapons for conversion into reactor fuel. As a consequence of this latter effort, it has been estimated that the equivalent of one lightbulb in every ten in the United States is powered by nuclear fuel removed from warheads previously targeted at the United States and its allies during the Cold War.
The U.S. Special Representative for Nuclear Nonproliferation agreed that nonproliferation and disarmament are linked, noting that they can be mutually reinforcing but also that growing proliferation risks create an environment that makes disarmament more difficult. The United Kingdom, France and Russia likewise defend their nuclear disarmament records, and the five NPT NWS issued a joint statement in 2008 reaffirming their Article VI disarmament commitments.
According to Thomas Reed and Danny Stillman, the "NPT has one giant loophole": Article IV gives each non-nuclear weapon state the 'inalienable right' to pursue nuclear energy for the generation of power. A "number of high-ranking officials, even within the United Nations, have argued that they can do little to stop states using nuclear reactors to produce nuclear weapons". A 2009 United Nations report said that:
The revival of interest in nuclear power could result in the worldwide dissemination of uranium enrichment and spent fuel reprocessing technologies, which present obvious risks of proliferation as these technologies can produce fissile materials that are directly usable in nuclear weapons.
According to critics, those states which possess nuclear weapons, but are not authorized to do so under the NPT, have not paid a significant price for their pursuit of weapons capabilities. Also, the NPT has been explicitly weakened by a number of bilateral deals made by NPT signatories, notably the United States.
Based on concerns over the slow pace of nuclear disarmament and the continued reliance on nuclear weapons in military and security concepts, doctrines and policies, the Treaty on the Prohibition of Nuclear Weapons was adopted in July 2017 and will be opened for signature 20 September 2017. Upon entry into force, it will prohibit each state party from the development, testing, production, stockpiling, stationing, transfer, use and threat of use of nuclear weapons, as well as assistance to those activities. It reaffirms in its preamble the vital role of the full and effective implementation of the NPT.
- 13 steps (an important section in the Final Document of the 2000 Review Conference of the Treaty)
- Comprehensive Test Ban Treaty (CTBT)
- Humanitarian Initiative
- Global Initiative to Combat Nuclear Terrorism (GICNT)
- List of countries with nuclear weapons
- Missile Technology Control Regime (MTCR)
- New Agenda Coalition (NAC)
- Non-Proliferation and Disarmament Initiative (NPDI)
- Nuclear armament
- Nuclear warfare
- Nuclear-weapon-free zone
- Multi-country zones
- African Nuclear-Weapon-Free Zone Treaty (Treaty of Pelindaba)
- Central Asian Nuclear Weapon Free Zone (Treaty of Semei)
- South Pacific Nuclear Free Zone Treaty (Treaty of Rarotonga)
- Southeast Asian Nuclear-Weapon-Free Zone Treaty (Treaty of Bangkok)
- Treaty for the Prohibition of Nuclear Weapons in Latin America and the Caribbean (Treaty of Tlatelolco)
- Other UN-recognized zones
- Multi-country zones
- Nuclear terrorism
- Proliferation Security Initiative (PSI)
- Renovation of the nuclear weapon arsenal of the United States
- Strategic Arms Limitation Talks (SALT)
- Strategic Offensive Reductions Treaty (SORT)
- Treaty on the Prohibition of Nuclear Weapons (also known as the Nuclear Weapon Ban Treaty)
- Weapon of mass destruction (WMD)