France on Tuesday test-fired its upgraded M51.3 nuclear-capable ballistic missile from a nuclear-powered submarine, with President Emmanuel Macron observing the launch as Paris continues to modernize its nuclear deterrent.

The missile was launched without a warhead from the Le Vigilant submarine off Brittany and landed in the North Atlantic, several hundred kilometres from any coastline, France's Defence Ministry said.

The ministry said the test was conducted in compliance with France's international obligations.

"The message has been sent loud and clear for wherever it must be received," Macron said in a video posted on X showing him watching the launch.

The test comes amid heightened tensions between Russia and Western countries over the war in Ukraine. Moscow has warned against what it considers potential threats to its Kaliningrad exclave, which borders NATO members Poland and Lithuania.

The M51.3 is the latest version of France's M51 submarine-launched ballistic missile and entered operational service in 2025. It is part of an ongoing program to modernize France's nuclear forces.

France does not disclose the missile's precise range. Public estimates put the M51 family at more than 9,000 km (5,600 miles), while French authorities say the M51.3 offers improved performance over earlier versions.

France maintains a nuclear deterrent based on submarine- and air-launched weapons. Four nuclear-powered ballistic missile submarines form the backbone of its sea-based force.

Macron said in March that France would strengthen its nuclear deterrent and proposed deeper consultations and cooperation with European allies on nuclear security.

France is also developing the next-generation M51.4 missile as part of its longer-term modernization program.

The Federation of American Scientists estimates France has about 290 nuclear warheads, making it one of the world's five nuclear-armed states. Paris has historically maintained a policy of nuclear deterrence centered on ensuring the country's ability to respond to an attack. (ILKHA)