Unpredictable policy decisions by Donald Trump and his skepticism toward NATO have strained transatlantic security ties and raised doubts about the reliability of the U.S. nuclear shield in Europe.
In response, Germany — particularly through its newly established National Security Council — has begun exploring ways to build a credible European nuclear deterrent that could complement the U.S. umbrella for as long as it remains in place.
As discussions evolve in Berlin, several parallel tracks are shaping the debate around European nuclear capabilities, especially those of France and the United Kingdom.
To start, long-running UK-France nuclear cooperation, underway since 2010, reached a new milestone with the Northwood Declaration in July 2025. For the first time, this agreement introduced the possibility of coordinating both countries’ nuclear forces.
A second track emerged in October 2024, when Germany and the UK signed the Trinity House Agreement. While intended to include nuclear-related discussions, this framework is still in its early stages.
Third, German Chancellor Friedrich Merz and French President Emmanuel Macron agreed to launch a Franco-German nuclear dialogue. A high-level steering group will oversee regular consultations and identify areas for cooperation.
A fourth initiative is expected to broaden these discussions to other European NATO members. Countries such as Poland, Denmark, Sweden, the Netherlands, Belgium, and Greece have already expressed interest. If the UK joins this expanded framework, it could evolve into a comprehensive European nuclear forum resembling NATO’s Nuclear Planning Group.
These efforts are still in their early phases, with the immediate goal of building shared understanding and aligning strategic objectives. The UK-France dialogue stands apart, as it allows two nuclear powers to engage on equal footing — discussing doctrines, sharing data, and coordinating operational approaches.
By contrast, the German-UK, German-French, and broader multilateral discussions are initially focused on information exchange and trust-building between nuclear and non-nuclear states — a necessary step before addressing more sensitive issues such as intelligence sharing.
The broader aim is not simply dialogue, but the gradual development of a credible European deterrent anchored in the capabilities of France and the UK, while maintaining ties to the U.S. nuclear umbrella for as long as possible.
Germany’s strategic thinking points to several next steps. Expanding bilateral talks to include more European partners is seen as essential to avoid concerns over dominance by Paris, London, and Berlin, and to address France’s traditionally independent nuclear posture. Including representatives from the U.S. and Canada would also help preserve the transatlantic connection.
Initially, discussions are likely to focus on political commitments — particularly whether nuclear powers are willing to extend security guarantees to non-nuclear allies. The UK already participates in such arrangements under NATO’s extended deterrence framework, whereas France has historically reserved its nuclear capabilities for national defense.
However, Emmanuel Macron has recently introduced the concept of “advanced deterrence” (“dissuasion avancée”), signaling a cautious shift toward a more collective approach without formally adopting extended deterrence.
Another area of focus could be the creation of consultation frameworks between nuclear and non-nuclear states in the event of a nuclear threat, similar to NATO’s Athens Guidelines. While final decision-making would remain with nuclear states, such mechanisms would ensure allies are involved in critical moments.
Non-nuclear countries could, in turn, contribute to the system — potentially through financial support. In Germany’s case, parliamentary research has already indicated that such arrangements could be legally viable.
Ultimately, any European nuclear deterrent would also depend on strong conventional military capabilities. As Europe’s largest economy, Germany would carry significant responsibility, while France and the UK would also need to balance their strategic and conventional roles.
Achieving this balance is likely to require difficult financial and political decisions, particularly in London and Paris, as they adjust national priorities to support a more integrated European defense posture.
