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Global cooperation on nuclear disarmament looks even further away
The Iran war inhibited progress at the Non-Proliferation Treaty Review Conference. But so did P5 countries’ resistance to talking seriously about disarmament.
Expert comment
Published 3 June 2026 —3 minute READ
Image — France’s Foreign Affairs Minister Jean-Noel Barrot at the 11th NPT Review Conference at UN Headquarters on 27 April 2026. (Photo by ANGELA WEISS / AFP via Getty Images)
Georgia Cole
Research Associate, International Security Programme
The 2026 Treaty on the Non-Proliferation of Nuclear Weapons (NPT) Review Conference concluded on 22 May without a consensus outcome document. It is the third time in a row that states parties have failed to agree on a review of the treaty’s implementation and progress, or to set out a plan to support and strengthen the treaty’s implementation. However, this failure was different from the last.
In 2022, it was Russia alone that blocked agreement, following its invasion of Ukraine. This year, multiple countries were prepared to hinder progress. The fractures ran across the ‘P5’ – the UN Security Council permanent members, all of whom are classed as ‘nuclear-weapon’ states and are the only countries permitted to possess nuclear weapons under the treaty. (Other nuclear armed countries are not parties to the treaty).
But what happened in New York was not a targeted disruption. It was the latest sign of a non-proliferation system under strain in an increasingly dysfunctional environment.
What broke down and why
The primary cause of failure was the Iran conflict. Countries could not agree on adding a paragraph addressing Iran’s non-compliance with its NPT obligations and stating that Iran could never acquire nuclear weapons. That remained bracketed in the final draft outcome document, meaning consensus had not been reached.
Conference President Đỗ Hùng Việt, whose management of an extraordinarily difficult process deserves credit, chose not to force states into a public confrontation on the issue. When he asked the conference to adopt at least a procedural consensus on strengthening the review process, Russia, China, and Iran blocked that too. Related workAvoiding a new nuclear arms race
Even if Iran had not been the breaking point, something else might have been. Other fault lines were close to the surface: Russia pushed for the deletion of text on North Korea’s weapons programme, prompting South Korean objections. Disputes over language on Ukraine’s Zaporizhzhia nuclear power plant, still under Russian occupation, remained unresolved.
A pattern is emerging, where review conferences become a forum for airing regional and bilateral grievances. That reflects a broader shift in how the major nuclear powers approach multilateral institutions.
When powerful states believe that their security interests are better served by bilateral leverage than by collective frameworks, consensus-based multilateral processes become difficult to sustain.
The disarmament deficit
The failure to agree a final document obscured another serious problem. Even the draft that was on the table represented a significant weakening of prior commitments.
New START, a US–Russia nuclear arms control agreement, expired in February with nothing to replace it. That leaves the world’s two largest nuclear arsenals without any agreed limits for the first time in over fifty years.
China’s nuclear build-up is accelerating. The US has threatened to resume nuclear testing and has accused both Russia and China of conducting tests. France has announced an expansion of its nuclear programme.
In this environment, the five recognized nuclear weapon states arrived in New York and set about forcing the removal of language calling on them to begin negotiations on disarmament – or even to pursue discussions urgently.
Nuclear weapons states removed even more mild requests from the outcome document – for more transparency and accountability on their part. The final draft vaguely called for constructive dialogue that might facilitate future progress. Many non-nuclear weapons states will interpret this as a signal – that beyond ensuring other countries do not acquire nuclear weapons, the P5 are no longer committed to the wider NPT regime.
Collective engagement can only do so much if the P5 are not listening.
The grand bargain at the heart of the NPT – that non-nuclear states forgo nuclear weapons in exchange for progress on disarmament by the P5 – is under severe strain, and the cracks are showing.
There were still meaningful signals from the wider membership. Countries pushed back against weakened disarmament language. There was strong opposition to any resumption of nuclear testing, with many states defending the Comprehensive Test Ban Treaty. The fact that so many non-nuclear states remained engaged and vocal matters. But collective engagement can only do so much if the P5 are not listening.
What comes next
The next NPT Review Conference is in 2031. The risk is that the underlying conditions deteriorate further during the intervening five years, proliferation pressures mount, and the case for investing political capital in the NPT becomes progressively harder to make.
Avoiding that outcome requires a practical assessment of what went wrong and what can be done differently.
An important lesson is that review conferences cannot be the primary forum for adjudicating active crises. When countries demand that a consensus-based multilateral process takes sides on contentious regional issues like the wars in Iran or Ukraine, deadlock is almost guaranteed.
An alternative is possible. In the leadup to the 1985 Review Conference, nuclear arsenals were almost at their Cold War height, Israel had destroyed a safeguarded nuclear reactor in Iraq, and there were serious non-proliferation concerns relating to several non-parties (such as South Africa and Brazil).
In this unsecure environment, the United States and Soviet Union famously set their differences aside and focused on strengthening the system by cooperating to reach consensus, rather than weaponizing it. That was a long time ago, but it is a reminder that cooperative behaviour during times of high geopolitical tension is possible.
The P5 need to strengthen engagement with one another on nuclear risk reduction through the ongoing ‘P5 process’ – a diplomatic forum between the countries. Dialogue has stalled in recent years. But this is a crucial route for progress on even modest confidence-building measures on doctrine, on new technologies, and on crisis communication.
The P5 demonstrating a willingness to engage in good faith, and treating the NPT as worth preserving, would itself send a signal. Seriously engaging with transparency and accountability initiatives put forward during the review conference would be a good start and is relatively low pressure and low-hanging fruit in terms of compliance.
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Article 2nd half
Non-nuclear weapon states committed to the treaty also need to coordinate more effectively and sustain pressure on the P5 beyond the NPT conference. Diplomatic pressure from a coherent, persistent bloc raises the political cost of obstruction. It will not transform P5 behaviour on its own, but it could shift the calculus.
A crucial time ahead
The NPT’s record on actual non-proliferation remains, by historical standards, impressive. The world has far fewer nuclear-armed states than analysts feared possible in the 1960s. The treaty continues to provide the legal and normative foundation for a global safeguards system that constrains proliferation and facilitates peaceful uses of nuclear energy.
But a treaty that cannot sustain its own institutional credibility will find it harder to underwrite the stability it was designed to protect. Three consecutive failed review conferences, against a backdrop of an accelerating arms race, expiring treaties, and mounting proliferation pressures, is not a temporary rough patch. The window for course correction is narrowing. States have five years to demonstrate they understand what is at stake.
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