PARIS — France test-fired an upgraded version of its M51 strategic ballistic missile from a submarine for the first time on Tuesday, a capability demonstration that President Emmanuel Macron called “very important” for the country’s strategic credibility and which he said would be monitored by allies and adversaries alike.
The nuclear-powered ballistic-missile submarine Le Vigilant fired an M51.3 missile in an acceptance test following the boat’s overhaul, the Ministry of the Armed Forces said in a statement. The missile, which didn’t carry a nuclear warhead, was launched off Finistère in western France and splashed down in the North Atlantic several hundred kilometers from any coastline, the ministry said.
France’s work to upgrade the M51 missile, manufactured by ArianeGroup, is part of a broader modernization of the country’s nuclear deterrence apparatus that also includes the construction of new ballistic-missile submarines and a future upgrade of the Rafale fighter jet that would carry a hypersonic nuclear cruise missile.
“This is a very important moment for our strategic credibility,” Macron told troops onboard a French Navy vessel from which he observed the launch on Monday. “Everything that has happened recently and what is happening today will be closely scrutinized by both our allies and our competitors alike, and it already is. Along the course we have set, this is a step forward.”
The modernization of France’s nuclear arsenal comes as the country works with several European allies on what Macron has called “forward deterrence,” a proposal that could involve extending the reach of French nuclear deterrence to those allies, although the details of what that would look like remain vague for now.
Every major overhaul of a French nuclear-powered ballistic missile submarine is followed by an acceptance test firing of the M51, the ministry told Defense News in an emailed response to questions.
ArianeGroup and France’s Directorate General for Armament completed a first flight test of the modernized M51 from a launch site in Biscarrosse in southwest France in 2023, and the new missile entered operational service in October last year.
The latest M51.3 variant is estimated to have a range of more than 9,500 kilometers, from more than 9,000 kilometers for the previous version, according to the Bulletin of the Atomic Scientists. The missile carries four to six multiple independently-targetable reentry vehicles, or MIRVs, according to the Bulletin.
While the official range of the missile is undisclosed, ArianeGroup says the M51 reaches an altitude of more than 2,000 kilometers before reentering the atmosphere at a speed of Mach 20.
The missile is equipped with the new TNO-2 oceanic nuclear warhead, and offers better performance in terms of range, accuracy and penetration capability, according to the ministry. The solid-propellant three-stage missile weighs more than 50 metric tons, and each of France’s four ballistic missile submarines can carry 16 of them.
“The M51.3 ensures the long-term credibility of the ocean-based component in the face of evolving adversary missile defenses,” the ministry said. “It reflects the commitment of the President of the Republic to maintaining operational credibility of the nuclear forces over the long term, at the level required by the international environment.”
The first version of the M51 was fired from the Biscarrosse launch site in 2006, with the first submarine launch from the SSBN Le Terrible in January 2010. Today’s launch was the seventh time a variant of the M51 was fired from a French submarine, and the 13th launch of the missile overall, all of them “of course, conducted without a nuclear warhead,” according to the ministry.
Rudy Ruitenberg is a Europe correspondent for Defense News. He started his career at Bloomberg News and has experience reporting on technology, commodity markets and politics.








