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The European Trilateral Track 2 Nuclear Dialogues, organized by the Center for Strategic and International Studies (CSIS) in partnership with the Royal United Services Institute (RUSI) and the Fondation pour la Recherche Stratégique (FRS), have convened senior nuclear policy experts from the United Kingdom, France, and the United States (P3) since 2009 to discuss nuclear deterrence, arms control, and nonproliferation policy issues. By identifying issues of mutual concern and areas of consensus, the group seeks to improve collaboration and cooperation among the three nations across a range of challenging nuclear policy concerns. The majority of the experts are former U.S., UK, and French senior officials; the others are well-known experts and academics in the field. Since the dialogue’s inception, currently serving senior officials from all three governments have routinely participated in the discussions.
Each year the Track 2 members of the group issue a consensus statement reflecting their discussions. All signatories agree to this statement in their personal capacities, which may not necessarily represent the views of their respective organizations. In 2024, the group’s discussion addressed a range of emerging strategic challenges for the P3, which are reflected in this statement of their consensus after the 2024 round of meetings.
The United States, the United Kingdom, and France hold common values and principles directed toward a shared purpose of sustaining global peace and security, as well as an understanding of their respective roles as responsible stewards of the nuclear order. While each of the three nations has unique perspectives and policies regarding nuclear issues and the nature of today’s security environment, as the three nuclear weapons states in the North Atlantic Treaty Organization (NATO) alliance, they play a unique and enduring role in the stewardship of international alliances and partnerships, especially in matters of nuclear deterrence, nonproliferation, and arms control.
2024 saw national elections in each of the P3 countries. While states may shift strategies, priorities, or resources to reflect the considerations of new national leadership, we are confident the P3 states will remain highly committed to continued cooperation with one another, their leadership roles within the wider alliance network, and maintaining the strength of NATO’s nuclear deterrent. This commitment is bolstered by a shared recognition of the increasing interconnectedness of the security environment: Each member of the P3 has overlapping and interdependent vital interests, threatened by adversaries that are collaborating at a scope and scale unprecedented in the post–Cold War world. While domestic political shifts may alter the way in which threats are addressed and managed, the appreciation of the threat posed by Russia, China, Iran, and North Korea transcends political change in the P3.
Russia, China, Iran, and North Korea increased both the breadth and depth of their collaboration over 2024. Russia and China’s 2022 “partnership with no limits” has been supplemented by the June 2024 Comprehensive Strategic Partnership Agreement between Russia and North Korea as well as the January 2025 Treaty on Comprehensive Strategic Partnership between Moscow and Tehran. Russia’s growing reliance on weaponry and personnel from North Korea to sustain its war in Ukraine, as well as its own increasing military activities in the Indo-Pacific, underlines the real strategic consequences of adversary cooperation. The rapid rise of Chinese capabilities in all domains is now a central concern for all members of the P3. The expectation that China will soon possess a stockpile of more than 1,000 nuclear warheads combined with the continued opacity of Chinese nuclear doctrine, and the Chinese military’s increasingly belligerent behavior regarding P3 military forces and Western allies in the Pacific, warrants consideration of the consequences for the United States and its P3 allies’ deterrence commitments: a problem further compounded by growing Chinese competitiveness in other domains such as sea and space.
As the P3 work to balance commitments in both the Euro-Atlantic and the Indo-Pacific, they recognize that greater security in one theater cannot be obtained by taking undue risks in the other. Adversary success in one theater would only embolden others elsewhere. Closer adversary collaboration increases the risks of enabling regional nuclear bullying, proliferation, and simultaneous conflicts, but such aggression can be deterred by credible signaling that the P3 along with other allies are prepared to confront and win conflict in two theaters simultaneously. The P3 should explore ways singly and together to make those aiding and assisting aggression and coercion suffer for such activity. Furthermore, to the degree Russian aggression in Ukraine is successful, expansionist policymakers in China, Iran, and North Korea will be emboldened.
While closer adversary collaboration has rightly prompted a discussion on what new systems and activities are required for the alliance to maintain its deterrent posture, the alliance must also ensure that new initiatives do not come at the cost of existing proficiencies in the alliance. NATO’s nuclear mission is foundational to European security, and any changes to alliance behavior, capabilities, or mission set must first and foremost uphold and serve the nuclear deterrence mission.
Russia continues to pose a significant threat to Euro-Atlantic security through its repeated escalation of the war in Ukraine and transition to an economy fully geared toward sustaining large-scale war, and President Putin’s repeated threats of using nuclear weapons. In turn, the sustainment, support, and optimization of NATO’s nuclear deterrence posture is essential. While the modernization of nuclear forces in the alliance remains a necessity, the alliance must also carefully consider the conventional assets that support the nuclear mission and enhance deterrence. Investments in deterrence-supporting infrastructure, air and missile defense, and deep-precision strike capabilities, as well as the integration of those systems across both the nuclear and nonnuclear members of the alliance, would greatly enhance the credibility and coherence of NATO’s deterrence posture.
There is great value for the P3 in investing now in supporting infrastructure, including pit production capacity, shipbuilding capacity, and other capacity-building measures. While these investments will not only aid in managing transition risk as allies modernize certain systems, they also serve to bolster NATO’s current deterrence posture and may disincentivize adversaries from attempting costly arms races if the alliance’s ability to compete is apparent. Current investments in submarine infrastructure in Barrow and in the surge capacity of U.S. pit production will have long-term deterrence payoffs justifying their costs. Similarly, NATO members should take advantage of the alliance-wide consensus regarding the renewed importance of air and missile defense and conventional precision strike to make serious investments in expanding and integrating NATO’s capabilities in both mission sets. Placing renewed emphasis on the conventional aspects of NATO’s deterrent would also encourage the non-nuclear members of the alliance to make lasting contributions to the alliance’s nuclear mission without taking it on themselves. A balanced division of labor in these domains would not only bolster NATO’s deterrence posture but also send a robust signal that the alliance remains united and clear-eyed regarding the nature of the threat it confronts.
In 2023, the bipartisan Congressional Commission on the Strategic Posture of the United States deemed the current U.S. strategic nuclear modernization program of record was necessary but not sufficient to meet the future threats faced by the United States. While the United States is the only member of the P3 to arrive at this conclusion regarding its national modernization track, the question of sufficiency is one that should be asked at the alliance level. The alliance has a strong understanding of threats to European security and strategic stability, and must now take steps to achieve a strategic posture, including a mix of conventional and nuclear capabilities, for the security environment. While arriving at the correct blend of capabilities and strategies will undoubtedly be a challenge, the successful modernization of the alliance’s strategic capabilities remains a no-fail mission.
In the evolving threat environment, the P3 commitment to uphold the norms that shape the global nuclear order and to implement their unique nuclear responsibilities is more critical than ever. The P3 have worked to raise awareness within the alliance regarding the threat to European security posed by adversary behavior; however, of equal importance is messaging outside of the alliance regarding the threat those same actors pose to the norms and institutions that underpin global security architectures.
It is a challenging moment for arms control, risk reduction, and transparency measures. While Cold War–era arms control looks to be increasingly unlikely, the P3 do not reject arms control outright, but rather are open to improving transparency with Moscow and Beijing and are taking steps to lay the groundwork for future arms control opportunities when the security environment improves. At the same time, there is much work to be done to reverse the deterioration of the norms and institutions that serve to control nuclear weapons globally. Combatting Russian and Chinese disinformation within the Nuclear Non-Proliferation Treaty (NPT), raising awareness to the ways in which adversaries cheat and conduct duplicitous diplomacy, alongside persistent positive engagement with the Global South are critical actions to preserve the global nuclear order.
In 2025, the P3 face a dynamic security environment with an enduring commitment to one another’s security. In managing the complexity of a changing environment, the direction of the P3 is guided by four key points. First, the alliance is clear-eyed with regards to the threats they face. Second, it is apparent that the alliance must modernize its arsenal to face the challenges of the day in both the nuclear and conventional domains. Third, the P3 are equally aware of the resourcing and coordination challenges that lie ahead and must now work to solve them. Finally, and most importantly, the P3 reiterate the value of the alliance and remain steadfastly committed to its success. In such a highly contested security environment, the value of coordination, cooperation, and commitment to one another is greater than ever.
The P3 nuclear community lost a longstanding and dearly held member this year. The nuclear communities of the United States, the United Kingdom, and France mourn the loss of John Harvey, and express their gratitude and admiration for the generosity with which he shared his wisdom. He will be missed.
This report is made possible by the generous support of the National Nuclear Security Administration.
