The 11th Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) takes place in April and May at the UN headquarters in New York.

On April 27, the 11th Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) began at the headquarters of the United Nations (UN) in New York, at a time of international tension marked by military escalations involving nuclear powers in violent conflicts around the world and reports of serious violations of International Humanitarian Law (IHL). The discussions will continue until May 22, and several civil society organizations have emphasized the need to highlight the humanitarian imperative during the debates, as well as gender, race, and class intersectionalities, for example, when analyzing the issue of the use and development of nuclear weapons. In this context, it is pertinent to understand the background of the treaty’s creation, the obligations assumed by the States Parties, and, furthermore, the demands presented by civil society.

What is the Treaty on the Non-Proliferation of Nuclear Weapons?

The Second World War ended days after the United States carried out nuclear attacks on Hiroshima and Nagasaki, Japan, in August 1945, which, by the end of that same year, had resulted in the deaths of between 100,000 and 200,000 people, constituting the only attacks involving the use of nuclear weapons in history. Following this event, not only the United States, but also Russia, China, the United Kingdom, and France sought to develop such weapons and began expanding their nuclear arsenals, strongly supported by the doctrine of nuclear deterrence, which is based on the idea that a credible nuclear retaliatory capability against potential adversaries discourages the use of such weapons by creating a scenario of Mutually Assured Destruction (MAD).

In this context, factors such as the 1962 Cuban Missile Crisis, the rapid expansion of nuclear testing around the world, and the intensification of the arms race during the Cold War highlighted the growing risks of international nuclear insecurity, driving the need for control mechanisms and leading to the creation of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Opened for signature in 1968, the NPT entered into force in 1970 with the aim of preventing the proliferation of nuclear weapons and weapons technology, promoting cooperation in the peaceful use of nuclear energy, and advancing the goal of nuclear disarmament.

First meeting of the Preparatory Committee for the Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons, United Nations, Geneva, Switzerland, 1974. (Audiovisual Library of International Law)

The treaty’s Article I categorically prohibits the five countries possessing nuclear weapons at the time — the United States, Russia, France, the United Kingdom, and China — from transferring their arsenals or assisting other countries in acquiring such weapons. Similarly, Article II prohibits non-nuclear-weapon States Parties from accepting transfers of such weapons, producing them, or receiving assistance in the manufacture of nuclear weapons.

Article IV establishes the peaceful use of nuclear energy as an inalienable right of the signatory countries, highlighting its potential applications in energy generation and the development of medicine. Thus, the exchange of knowledge and nuclear material with non-nuclear-weapon States is permitted, provided that its purpose is use in civilian nuclear programs, which are monitored by the International Atomic Energy Agency (IAEA). Through inspections, it is therefore ensured that nuclear materials are not used for military purposes. Although they are distinct entities, the NPT and the IAEA operate in an integrated manner and, as stated in Article III, the Agency monitors compliance with the obligations of the States Parties to the treaty, bearing the responsibility of reporting suspicious or undeclared activities directly to the UN Security Council.

“Each non-nuclear-weapon State Party to the Treaty undertakes to accept safeguards, as set forth in an agreement to be negotiated and concluded with the International Atomic Energy Agency in accordance with the Statute of the International Atomic Energy Agency and the Agency’s safeguards system, for the exclusive purpose of verification of the fulfilment of its obligations assumed under this Treaty with a view to preventing diversion of nuclear energy from peaceful uses to nuclear weapons or other nuclear explosive devices.” Excerpt from Article III.1 of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT).

Currently, the treaty has 191 States Parties and, among nuclear-weapon states, three have never joined the treaty: India, Israel, and Pakistan. North Korea, which also possesses nuclear weapons, officially announced its withdrawal from the treaty in 2003.

States Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (United Nations)

NPT and TPNW: what are the differences?

The NPT is commonly confused with the TPNW, the Treaty on the Prohibition of Nuclear Weapons (2017), and it is therefore important to establish the differences between these legal frameworks. The NPT, as mentioned above, constitutes a nuclear arms control treaty aimed at preventing more countries from acquiring nuclear weapons, but it does not strictly prohibit the possession of such weapons by countries that already possess them. The TPNW, by contrast, is a universal prohibition framework applicable to all its States Parties, creating a new legal standard in the field of international disarmament by prohibiting the development, testing, production, acquisition, possession, stockpiling, transfer, use (or threat of use) of nuclear weapons. 

The Treaty on the Non-Proliferation of Nuclear Weapons remains one of the main pillars of contemporary international security, as it establishes commitments related to non-proliferation, nuclear disarmament, and cooperation in the peaceful use of nuclear energy. However, the international nuclear regime faces significant challenges that must be highlighted, such as the modernization and/or expansion of the arsenals of nuclear-weapon states (including the integration of Artificial Intelligence into nuclear weapons systems) and current geopolitical tensions marked by the risk of nuclear proliferation and increasing mistrust between States.

What does civil society say?

In this context, civil society organizations are organizing and mobilizing during the 11th NPT Review Conference with the aim of pressuring States Parties to comply with the commitments assumed under the treaty, especially those related to nuclear disarmament. Through campaigns, side events, and the publication of statements, these groups seek to broaden civil society participation in multilateral discussions, strengthen transparency in negotiations, and highlight the humanitarian impacts of nuclear weapons.

The International Campaign to Abolish Nuclear Weapons (ICAN) highlights the non-compliance of the originally five nuclear-armed States with Article VI, which establishes the obligation to pursue nuclear disarmament in good faith. According to the campaign, “[...] following a reduction in arsenals by the US, Russia, France and the UK following the end of the Cold War, those countries, plus China, are all modernising their arsenals and are either expanding them or have plans to do so, which is the opposite of what they should be doing under the treaty.” ICAN also reiterates that policymakers in some non-nuclear States, especially European NATO members, are discussing accepting “nuclear protection” from France or even developing their own nuclear weapons. In this context, the NPT’s disarmament pillar is affected by countries that prioritize national interests over their legal obligations and the security of humanity.

The International Physicians for the Prevention of Nuclear War (IPPNW) emphasized in a statement published on its official website that there is no humanitarian response to any use of nuclear weapons, and that even a single detonation would result in hundreds of thousands of deaths and severe injuries. The organization, in agreement with ICAN, called on nuclear-armed States to “take responsibility for our collective future, and fulfill your Article 6 obligations in good faith.” From a feminist and decolonial perspective, the Women’s International League for Peace and Freedom (WILPF) highlights in a statement to the Review Conference that “The long-term health effects of radiation, the destruction of livelihoods, and the diversion of public resources toward militarisation instead of social needs all reinforce existing gender inequalities. These harms are intersectional, shaped by age, race, class, colonial history, and minority status.” In this sense, the organization urges countries to understand that nuclear disarmament is an essential component in achieving gender equality and sustainable peace.

What are the challenges of the NPT Review Conference?

In light of this scenario, the increasing difficulty of NPT Review Conferences in reaching consensus highlights the challenges faced by the current international nuclear disarmament regime. The absence of consensus final documents in the 2015 and 2022 conferences, combined with concerns regarding the 2026 meeting, demonstrates not only the complexity of multilateral negotiations in a geopolitically tense international context, but also the persistence of disagreements among States regarding the implementation of commitments under Article VI of the treaty.

Furthermore, as mentioned above, the current scenario is accompanied by the continued modernization of nuclear arsenals and the rise of narratives that reinforce the centrality of nuclear weapons in the national security strategies of some States. This context contributes to increasing concerns about the effectiveness of international disarmament mechanisms and about the NPT’s capacity to deliver concrete progress after more than five decades of existence. In this sense, it reinforces the importance of civil society, international organizations, and non-nuclear-weapon States in advocating for concrete, verifiable, and transparent measures aimed at nuclear disarmament and the construction of an international security system based on peace and cooperation.

Dhesarme, in this context, reaffirms that the construction of international peace depends on strengthening nuclear disarmament, holding nuclear-armed States accountable, and ensuring effective commitment to International Humanitarian Law (IHL). The existence of nuclear weapons threatens the very survival of humanity, as a human error, technical failure, or cyberattack could lead to an irreversible catastrophe. Therefore, the urgent need for States Parties to comply with their obligations under all articles of the NPT is reiterated.

Written by: Júlia Marcon

Reviewed by: Fernando Fiala

References

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INTERNATIONAL CAMPAIGN TO ABOLISH NUCLEAR WEAPONS. ICAN addresses NPT Review Conference with nuclear risks at highest ever level. ICAN, 1 May 2026. Available at: https://www.icanw.org/ican_addresses_npt_review_conference_with_nuclear_risks_at_highest_ever_level. Accessed: 06 May 2026.

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WOMEN’S INTERNATIONAL LEAGUE FOR PEACE AND FREEDOM (WILPF). Statement of the WILPF Working Group on Disarmament for the 2026 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons. Available at: https://www.wilpf.org/wp-content/uploads/2026/04/Port-NPT-DWG-Declaration.pdf. Accessed: 06 May 2026.