French President Emmanuel Macron said France will increase the number of its nuclear warheads and deepen defence cooperation with several European partners to strengthen continental security amid rising geopolitical tensions.

Speaking at the Ile Longue nuclear submarine base, Macron outlined an updated nuclear doctrine aimed at reinforcing deterrence as Russia’s war in Ukraine continues and concerns grow over long-term security guarantees for Europe. He described the plan as the gradual implementation of an “advanced deterrence” strategy designed to respond to multiple threats while preserving France’s strategic sovereignty.

Macron said the expansion of France’s nuclear arsenal was necessary to bolster Europe’s defence posture, but added that Paris would no longer publicly disclose details about its stockpile. France is estimated to possess around 290 nuclear warheads, making it one of Europe’s two nuclear powers alongside Britain.

The French leader also announced that eight European countries — including Germany, Britain and Poland — have agreed to participate in a coordinated deterrence framework. Under the proposal, partner states could host elements of France’s strategic air forces, allowing deployment across the continent to complicate potential adversaries’ calculations. The plan may also involve conventional military participation by allied forces in nuclear-related exercises.

Macron warned that escalating conflict involving the United States, Israel and Iran could create broader instability with potential implications for Europe’s security environment.

The announcement comes amid political uncertainty ahead of France’s next presidential election, with concerns among European allies that a potential victory by the far-right National Rally led by Marine Le Pen could affect European defence cooperation.

Analysts from European policy institutions have cautioned that building a unified continental nuclear deterrent would require deeper political integration than currently exists, though they argue Europe must increasingly develop independent strategic thinking rather than relying primarily on the United States.

France’s Ile Longue base houses the country’s four nuclear-powered ballistic missile submarines, with at least one vessel continuously deployed at sea to maintain deterrence readiness.