France has begun development of a new nuclear ballistic missile M51.4, which will cost 7.5 billion Euros.

Sept 2025 : The development of a new version of the M51.4 intercontinental ballistic missile for French strategic submarines has officially begun. This was officially announced by French Defence Minister Sebastian Lecornu, adding that “an autonomous and sovereign deterrence potential is the foundation of the defence system“. The new version of the M51.4 is intended for France’s new strategic submarines under the SNLE 3G project.

The main feature of the M51.4 ICBM should be a longer range, accuracy and the ability to penetrate missile defence systems even more effectively than the latest current version, the M51.3. Neither the development timeline nor a detailed list of updates have been announced yet. But we are talking about a rather distant prospect.

For example, the M51.3 version has been under development since 2014, and its production is only scheduled to begin this year. Also, such development is not cheap at all, and an estimated 7.5 billion euros are being earmarked for modernization, as indicated by the budget request for the current year.

It is the M51.4 that will be used in France’s new submarine missile carriers, which are currently being developed under the SNLE 3G project and which are to replace the Triomphant. It is predicted that the first new submarine under this project will enter service around 2035, which is quite relevant to the expected development period of a new version of the intercontinental ballistic missile. It should be noted that the SNLE 3G, like the Triomphant, is to carry 16 such missiles. The plan for the construction of these strategic submarines provides for the creation of four units with a 1:1 replacement, as well as their operational life until the 2090s.

In general, the M51 missile development program began in 1998, the first launch was in 2004, and it entered service in 2010. It is a three-stage solid-fuel missile with a launch weight of about 53 tons and an estimated range of over 8,000 km. Its first version, the M51.1, was equipped with 3-6 separate TN-75 nuclear warheads of 150 kt each.

In the M51.2, they were replaced by new TNO (Tête Nucléaire Océanique) of similar power or 100 kt. These warheads have a greater chance of overcoming enemy missile defences. The deployment of this version began in 2016. The M51.3, which is only now starting to be deployed, should receive an updated TNO-2 charge and even greater chances of breaking through ABM, as well as a slightly longer range.

Team Maverick