France has conducted the first submarine launch of its new M51.3 nuclear-capable ballistic missile, marking a major test of its sea-based nuclear deterrent. The missile was launched from the nuclear-powered ballistic-missile submarine Le Vigilant and travelled over the North Atlantic before impacting hundreds of kilometres from any coastline, France’s Defence Ministry said.

French President Emmanuel Macron watched the launch from the multi-mission frigate Auvergne. The Direction générale de l’armement tracked the missile throughout its flight, with the trials ship Monge also involved in monitoring the test. The ministry said the missile carried no nuclear warhead and that the launch complied with France’s international commitments.

The ministry described the test as proof of “the excellence of the high-tech solutions employed by French industry in the field of nuclear deterrence.” Built by ArianeGroup, the M51.3 entered service on October 24, 2025. Its earlier qualification flight was conducted from a land-based site in November 2023.

Macron wrote on X: “Aboard the multi-mission frigate Auvergne, I witnessed the first firing of the new M51.3 ballistic missile from the nuclear-powered ballistic missile submarine Le Vigilant. Very few nations possess such expertise. Congratulations to all the players in this exceptional achievement: DGA, CEA, Ariane Group, Naval Group, and the French Navy.

“Your professionalism, your rigour, and your technical mastery are the pride of France. This technical success is a new demonstration of the credibility of our deterrence, whose sustainability is assured. To be free, one must be feared. And to be feared, one must be powerful. To protect the French in the long term against threats, I launched the renewal of our capabilities for the decades to come as early as 2017. In ten years, the budget for our armed forces will have doubled.

“Our future strategic submarines are currently under construction. This year, we launched the program for hypersonic and manoeuvrable strategic missiles, which will equip our airborne deterrence component. Our nuclear deterrence protects us and will continue to protect us. Long live the Republic, and long live France.”

Tuesday’s test also completed Le Vigilant’s requalification after a major refit. A navigation warning had closed an area southwest of Penmarc’h from October 5 to 21. Witnesses reported seeing the missile emerge from the sea shortly after 9:10 am, followed by a contrail and sustained rumbling.

The M51 is around 12 metres long, 2.3 metres wide and weighs about 52 tonnes. It uses three solid-propellant stages and has an estimated range of 8,000 to 10,000 kilometres. It can reach speeds close to Mach 20. The M51.3 is designed to carry the newer TNO-2 oceanic warhead. Analysts estimate it can carry four to six independently targetable warheads, though exact capabilities remain classified.

The M51 equips France’s four Triomphant-class submarines, with one continuously deployed at sea. ArianeGroup says the missile can travel into space at altitudes above 2,000 kilometres before re-entering the atmosphere at Mach 20. France has also contracted ArianeGroup to develop the M51.4. The next-generation SNLE 3G submarine programme is underway, with the first vessel expected in the mid-2030s.