The Exacerbation of Longstanding Structural Tensions: The 11th NPT Review Conference Closes without an Outcome Document

From April 27 to 22 May 2026, the 11th Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) was held in New York amid a climate of considerable tension. In a context marked by the ongoing Russian war against Ukraine, the U.S.-Israeli war against Iran, concerns about a possible nuclear arms race between the United States, China and Russia, as well as growing frictions over nuclear sharing arrangements, dissatisfaction over the lack of progress on nuclear disarmament, and persistent non-proliferation concerns, the states parties were deeply divided and the debates around key issues highly polarised. For the third time in a row, following the inability of the 2015 and 2022 Review Conferences to reach consensus, the 2026 Conference closed without any outcome document.

Despite some causes for disagreements seeming circumstantial, the protracted inability of the states parties to reach consensus, illustrated by the failure of the 11th Review Conference to produce an outcome document, shows deeply rooted structural tensions permeating the NPT regime as a whole. The divisions that led to the inability to reach an outcome document are, for the most part, not new, only exacerbated. This post analyses how current contextual tensions take place against a background of underlying divisions that have been deeply embedded in the NPT system.

A Multicausal Failure to Reach an Outcome Document

As emphasised by the President of the Review Conference, Ambassador Do Hung Viet, the failure to reach an outcome document was not caused by a single state or group of states, but rather by the substantial absence of consensus on several key points which would have led one state or another to block consensus if an outcome document had formally been submitted for adoption. The deep divisions among the states parties are particularly apparent in the statements they made during the closing plenary meeting.

The group of the Non-aligned states parties to the NPT, the Association of Southeast Asian Nations, the Arab group, the African group, and the New Agenda Coalition as well as several individual states, expressed in various forms deep concerns over the lack of progress on nuclear disarmament under Article VI of the NPT and over the reluctance of nuclear-weapon states (NWS) to recognise themselves bound by the lists of measures included in the final documents of the 1995, 2000 and 2010 Review Conferences. For these states, the weakness of the language on disarmament contained in the final version of the draft outcome document was a serious obstacle to consensus. This phrasing of the latest version of the outcome document was, however, in turn caused by the opposition of the nuclear-weapon states to any stronger affirmation of commitments on this point.

Similarly, a number of states, in particular the United States, the United Kingdom, Australia, Canada, as well as the European Union member states, expressed dissatisfaction over the inability to reach an agreement on a wording strongly condemning Iran’s violations of its safeguards agreements. They were joined by Japan in condemning the absence of mention of Russia’s war against Ukraine, its nuclear threats and its seizure of Zaporizhzhia Nuclear Power Plant, and of the Democratic People’s Republic of Korea’s (DPRK) continuing nuclear and missile programs, a point also mentioned by the Republic of Korea as an obstacle to consensus. In turn, the absence of mention of the situation in the DPRK and in Ukraine was caused in particular by the opposition of Russia to any such mention. As for the situation in Iran, any consensus on highlighting its violations of its safeguard agreement would in any case have been blocked by the opposition of Iran itself.

Thus, the causes for the failure to reach an outcome document were many and the states parties appear highly divided. This polarisation, however, is not new and was already at the heart of the failure of the previous Review Conferences to reach outcome documents.

Longstanding Issues Left Unsolved

The disagreements formulated during the 11th Review Conference express deeper divergences over the NPT regime as a whole and especially over the balance of rights and obligations for the different categories of states, NWS on the one hand, and non-nuclear-weapon states (NNWS) on the other. This disagreement is particularly reflected in polarised interpretations of Article VI of the Treaty. This article reads: “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 strict and effective international control.”

This article is the only inclusion of obligations regarding nuclear disarmament in the core of the Treaty and is therefore the sole basis for NWS disarmament obligations. States, however, have always interpreted this article in different ways, those in favour of the complete elimination of nuclear weapons interpreting it in a strong way, seeing ‘disarmament’ as the actual complete elimination of nuclear weapons, and those in favour of nuclear deterrence interpreting it in a much weaker way, seeing ‘disarmament’ broadly as a process aiming at reducing the number of nuclear weapons without necessarily leading to their elimination, or putting this aim so far in the future it has no impact on the present.

At present, both interpretations point to a lack of progress on nuclear disarmament, due to the collapse of arms control regimes and to the resurgence of a nuclear arms race. However, it would be completely possible for the NWS to restore arms control without further committing to the actual elimination of nuclear weapons. The return to arms control would allow the containment of the nuclear arms race, and the restoration of strategic stability, in a world that would remain nuclear armed. Discussions on arms control are indeed probable as they will appear to be the only way forward to avoid a collapse into nuclear war.

The return to arms control and strategic stability, however, would not, by itself, solve the underlying issue of the continuation of possession of nuclear weapons by NWS, and the frustrations of a number of NNWS at the lack of progress on disarmament. Arms control has indeed existed in the past without leading in any way to the complete elimination of nuclear weapons.

Whereas the need for some sort of avoidance of an unchecked nuclear arms race seems to be widely agreed upon, the NWS have always proven very reluctant to accept interpretations of the Treaty that would meaningfully bind them to take action towards the elimination of nuclear weapons. For example, the lists of measures included in the outcome documents of the 1995, 2000 and 2010 Review Conferences are not considered to be legally binding by the NWS and their allies, which means that they do not consider their lack of progress on these measures to constitute, in itself, proof of non-compliance with Article VI.

This situation creates a lot of frustration among numerous NNWS which consider that the so-called “grand bargain” of the NPT, by which NNWS renounced nuclear weapons in exchange for a protection of their right to the benefits of peaceful nuclear energy and the commitment of NWS to eliminate their nuclear weapons, is not being fulfilled. These tensions date back to the very negotiation and adoption of the Treaty and have remained unsolved ever since.

Conclusion: What Future for the NPT?

As has become usual in the last 15 years, the question of the future of the NPT system keeps being asked. If it remains to be seen whether the regime will eventually collapse or if it will keep standing despite the tensions it faces, it should be noted that most of the states parties reiterated their attachment to it, in spite of the conflicts and the disagreements. It seems that no state considers that it would really benefit from a collapse of the regime as a whole. Despite the disagreements and the dissatisfactions, especially among the NNWS that are not part of nuclear alliances, the NPT has helped prevent further nuclear proliferation which would have been a source of instability and insecurity for most states.

In his last address to the Conference, Ambassador Viet warned that he was “increasingly convinced that the real threat lies not in continuing to drive in circles, but in reaching a dead end”. Of course, the collapse of the regime remains a possibility, in the event of cascading nuclear proliferation, or of nuclear war. But, as long as the NWS do not overturn the status quo, for example, by using a nuclear weapon or by helping new states to develop nuclear weapons, the balance of power seems, for the time being, so unequal that it is hard to imagine any change in the situation by which they would agree to genuinely commit to obligations leading to the actual and foreseeable elimination of nuclear weapons. It is thus highly possible that the regime will indeed keep on running in circles for a long time.