France conducts first test launch of M51.3 submarine-launched ballistic missile

Paris, France. France’s defence ministry said on Tuesday it had conducted the first test launch of its latest-generation M51.3 submarine-launched ballistic missile. The test underscored France’s nuclear deterrent amid heightened tensions with Russia.

Launch off Brittany

The missile was launched off the coast of Brittany to certify the nuclear submarine Le Vigilant’s ability to deploy the weapon following a major maintenance overhaul, the ministry said in a statement.

The M51.3 carried no nuclear warhead or other payload, and the launch was conducted in strict compliance with international obligations, the ministry said.

The M51.3 is the latest version of the missile that entered service in October 2025 as part of the modernisation of France’s nuclear deterrent.

Tensions with Russia

The ministry’s announcement did not mention Russia. However, the test followed President Vladimir Putin’s warning last week that the West should not escalate the standoff over Ukraine by threatening the Russian exclave of Kaliningrad.

Kaliningrad lies between EU members Poland and Lithuania. Moscow has made clear that it would defend the territory with nuclear weapons if necessary.

NATO has said none of its “exercises or activities pose a threat to the territory of the Russian Federation”. Putin also said Russia had no plans to attack any European country and wanted to coexist peacefully.

Macron’s nuclear defence initiative

“Today we are stronger. The message has been sent loud and clear for wherever it must be received,” President Emmanuel Macron said in a video posted on X showing him watching the launch.

Macron said in March that France would expand its nuclear arsenal. He also launched an initiative offering European partners joint exercises, the possible short-term deployment of nuclear-capable assets on allied territory and deeper consultation.

Since then, readiness to bear the costs of defending France’s values and security has remained a constant theme of his messaging.

France’s nuclear arsenal

France spends roughly €5.6 billion ($6.04 billion) a year to maintain its stockpile of 290 submarine- and air-launched nuclear weapons, the world’s fourth-largest arsenal.

Britain has 225 nuclear warheads, while Russia and the United States have more than 5,000 each.