The image accompanying this post is created by the artist Wakana Yamauchi, one of several original artworks produced for the 63rd Pugwash Conference which adorned the walls of the conference venue.
Statement of the Pugwash Council, issued following the 63rd Pugwash Conference, Hiroshima, 1-5 November 2025
The Pugwash Council is honoured to have met in Hiroshima to commemorate 80 years since the atomic bombing of this city as well as Nagasaki. We pay tribute to the Hibakusha – the survivors and victims of those attacks – whose voices we have heard and we heed. As we reflect on the challenges to international security today, from this city which bears witness to the disaster of nuclear weapons, the Pugwash Council reaffirms the founding vision of the Pugwash Conferences: that the abolition of nuclear weapons is necessary, now more than ever, in pursuit of a world free of war.
In recent years, the most worrying trend we observe is the dramatically diminishing reliance on cooperation, diplomacy, and dialogue in favour of competition, confrontation, and war. We caution that, as international law is routinely ignored and the international system faces increasingly severe strain, countries face an insecure world not seen since the early days of the Cold War. Such conditions will inevitably increase the risk of intentional or unintentional nuclear weapons use and are likely to stimulate a dangerous increase in demand for deterrence through nuclear weapons. As the Russell-Einstein Manifesto reminds us, we must chart a different path and learn to think in a different way: away from the threats of massive death and destruction offered by such weapons, towards a new paradigm of peace, security, justice, and dignity for all humankind.
The Pugwash Council takes note of the following topics which were discussed in detail by the conference working groups, the reports of which contain concrete recommendations.
Global Nuclear Dangers
In 2025, nuclear dangers are characterized by a resurgent nuclear arms race and heightened risks in several regional conflicts. Russia and the United States, together holding about 90 percent of the world’s 12,240 nuclear warheads, maintain large stockpiles while modernizing and diversifying their capabilities. This modernization includes expanding the roles of non-strategic nuclear weapons and potentially increasing the number of deployed warheads if the expiration of the New START treaty in early 2026 is allowed to happen. The global nuclear order is being stressed by the expansion and modernization programs, including theatre-range dual-capable delivery systems, of all nuclear armed states.
The Pugwash Council supports initiatives which work to prevent a new and dangerous unfolding arms race.[2] All nuclear-armed states—including those not party to the Nuclear Non-Proliferation Treaty (NPT)—have a responsibility to reduce, and ultimately eliminate, the threat posed by nuclear weapons, including reaffirming their obligation not to test nuclear weapons. Efforts should focus on achieving substantial reductions in nuclear arsenals in the short-term; in the longer term, states must seek the total elimination of nuclear weapons in line with the Treaty on the Prohibition of Nuclear Weapons (TPNW). In parallel, states should seriously explore the adoption of robust No First Use (NFU) policies. Future arms control should move beyond counting warheads or launchers and instead focus on specific systems and doctrines. Development and deployment of new missile defence systems should be put on hold, and space must remain free from any weapons. The five nuclear weapons states of the NPT must engage in regular, substantive discussions with greater ambition, including on their respective nuclear weapons doctrines. The Pugwash Council supports the UN Independent Scientific Panel on the Effects of Nuclear War and stands ready to play a key role in mobilizing scientists, especially younger generations. The Pugwash Council is deeply concerned by recent statements to resume nuclear testing, which risk igniting a new arms race and triggering nuclear proliferation, and calls for the earliest possible entry-into-force of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), allowing the full functioning of its International Monitoring System.
Emerging and Disruptive Technologies
Global dynamics and deterrence are also shaped by rapid technological advancements, including artificial intelligence (AI), cyber capabilities, space and quantum technologies, and long-range precision conventional systems. These potentially increase risks of accidental or unintended conflict due to shorter decision-making timelines and new vulnerabilities. AI provokes novel concerns in the field of synthetic biology, which are exacerbated by the absence of verification mechanisms within the Biological and Toxin Weapons Convention; equally, AI may also assist with the discovery of new highly toxic molecules, an emerging challenge state parties must address under the Chemical Weapons Convention. The privatization of space is complicating any effort to seek deeper regulatory clarity, potentially destabilizing this critical domain and fuelling an arms race, to the detriment of all nations.
There is a strong need to establish common understandings of the different applications of artificial intelligence and quantum technologies to nuclear systems and other military assets before specific standards, regulations and control can be set. The development of agreements to prohibit attacks on objects in space, operational space traffic regulations and avoidance through emergency communication channels, space situational awareness, and cooperative security measures should be promoted by the international community. An assessment of the implications of the Golden Dome project and space-based ballistic missile defense technologies is urgent. Fostering discussions on understanding AI and its applications, standards, regulations and control will help to increase coupling between high-level policy and decision makers and technical programme managers in the industry.
Regional Conflicts and Escalatory Pressures
Several regional conflicts represent theatres where nuclear risks are acute and where rapid change may impact the incentives for nuclear and WMD acquisition.
The erosion of the broader arms control architecture—including the termination of the INF-Treaty, the Treaty on Conventional Armed Forces in Europe, the Open Skies Treaty and strategic weapons agreements—has been a fundamental trigger of insecurity in Europe. The war in Ukraine has seen a resurrection of nuclear coercion as a tool of statecraft. Such nuclear threats are deeply destabilizing and can precipitate inadvertent escalation due to weak channels of communication. Any ceasefire in the war, albeit welcome and necessary, would be temporary unless accompanied by a credible long-term strategy for peace and resolution of fundamental security concerns, which should be achieved by dialogue and confidence-building exchanges. European states are caught between a reluctance for strategic autonomy and a seeming retrenchment of US interest in the continent.
In the Middle East, an unprecedented period of war and aggressive military confrontation has shifted the region dramatically. Israel’s security cannot be achieved without the creation of a viable and peaceful Palestinian state, supported by regional actors and the international community. The Pugwash Council stresses the urgent need to uphold the Gaza ceasefire, accelerate humanitarian assistance, and ensure that any international security presence operates under a clear UN mandate. Lasting peace must be grounded in international law, accountability, and inclusive reconstruction efforts, with a determination toward a two-state solution. A viable agreement to reduce concerns over Iran’s nuclear program remains achievable: Iran should verifiably reaffirm its NPT obligations, commit not to withdraw from the Treaty, restore full cooperation with the IAEA, and eliminate its 60% enriched uranium stockpile under international oversight, while the United States and the E3 must reciprocally provide calibrated sanctions relief to enable a comprehensive and enforceable settlement. Any durable accord should allow only limited, peaceful uranium enrichment under rigorous and permanent IAEA verification. All efforts should be devoted to avoiding Iran withdrawing from the NPT. This would gravely undermine the global non-proliferation regime, destabilize the Middle East, and risk prompting other states to reconsider their nuclear policies. The Pugwash Council stresses that any military attack on nuclear facilities, as well as the targeted killing of nuclear scientists, constitutes a grave breach of international humanitarian law: it contravenes the core protections of Article 56 of Additional Protocol I to the Geneva Conventions and violates the fundamental principle that civilians and civilian infrastructure may never be made the object of attack. The Pugwash Council emphasizes the importance of rebuilding trust and fostering regional cooperation through education, dialogue, and the establishment of a new security framework to curb arms proliferation and advance the goal of a Middle East free of nuclear weapons as well as of other weapons of mass destruction.
In East Asia, increasing tensions between China and the US is altering threat perceptions and consequently reordering policy options in many regional states. There remains a fundamental need for China and the U.S. to start a dialogue based on principles of mutual respect, equality and undiminished security which identifies transparency and confidence-building measures to forestall a potential crisis. The unresolved DPRK nuclear situation must be addressed through engagement of the key players in a more creatively-framed risk reduction dialogue.
In South Asia, the four-day military conflict in May 2025 reminds us of the continuing risk of escalation to nuclear war in the region The Pugwash Council underscores that open channels of communication and crisis management are essential to prevent escalation and restore confidence building measures to stabilize the region.
Recognizing these many risks, the Pugwash Council firmly asserts that the international community has a collective responsibility to not only implement past agreements but to adopt positive and effective measures that will eliminate nuclear and other WMD dangers, curb proliferation, address regional insecurity, and reduce antagonism. Scientists and technical experts, as inspired by the Pugwash tradition of policy dialogue, remain essential actors in providing evidence-based analyses and foresight, advocating for arms control, and educating policymakers and the public about nuclear dangers.
Broader political steps would include:
- Engaging in diplomatic paths to conflict resolution: Addressing root causes of regional conflicts, reducing security concerns through dialogue, and committing to peaceful dispute resolution can lower incentives for nuclear coercion and proliferation.
- Promoting multilateral solutions to reduce the salience of nuclear weapons: A priority is to also pursue P-5 dialogue and a broader set of discussions which recognizes that the modern nuclear landscape, with new technologies and multiple actors, demands innovative frameworks beyond traditional numerical limits.
- Reinvigorating non-proliferation mechanisms: The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and the Treaty on the Prohibition of Nuclear Weapons (TPNW) provide legal and normative bases for disarmament. Encouraging universal adherence and effective implementation of these treaties supports the international rule of law and the denuclearization agenda.
- Seeking coordinated restraint in the application of emerging technologies to weapons systems: The integration of AI, cyber, and quantum technologies into nuclear and warfighting strategies requires new norms and potentially treaties to avoid destabilizing arms races.
- Enhancing verification and transparency measures: Further improvement of International Atomic Energy Agency (IAEA) safeguards and accelerated entry-into-force of the Comprehensive Nuclear Test Ban Treaty (CTBT), complemented by new technologies for monitoring nuclear activities, can deter clandestine programs and build confidence in the principle of non-proliferation.
- Enhancing safety, security and safeguards of peaceful nuclear energy cooperation: Support of inalienable rights for civilian uses of nuclear technology in accordance with non-proliferation commitments and robust nuclear safety and security frameworks can help to reduce global carbon emissions.
- Strengthening disarmament and verification frameworks governing chemical and biological weapons: A rational source of scientific analysis of contemporary threats in this field, including resources in different languages, verification concepts and codes of conducts are necessary.
The world today stands at a critical juncture in confronting the enduring and evolving dangers posed by nuclear weapons, marking the 80th anniversary of the atomic bombings of Hiroshima and Nagasaki. Pugwash, as a movement of scientists, continues to alert the world to escalating risks, to propose technical solutions for arms control, disarmament, and proliferation challenges, and to promote confidence- and security-enhancing dialogue in all areas where conflict and war threaten peace and humanity.
[1] See (1) the Nobel Laureate declaration, issued by the Bulletin of Atomic Scientists https://thebulletin.org/2025/07/the-nobel-laureate-assembly-declaration-for-the-prevention-of-nuclear-war/
(2) the Elders Statement: https://theelders.org/news/elders-publish-new-policy-paper-nuclear-weapons,
(3) the Call to Halt and Reverse the Nuclear Arms Race, issued by more than 20 US NGOs: https://reversethearmsrace.wordpress.com/ and (4) 2024 UN Secretary-General António Guterres: https://press.un.org/en/2024/sgsm22261.doc.htm
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