Britain confirms it is developing the Astraea nuclear warhead.

The UK Ministry of Defence has confirmed that it is developing a new nuclear warhead model codenamed Project Astraea. This is part of London's " Defence Strategy Review 2025" program aimed at enhancing nuclear deterrence capabilities.

In response to questions from the British Parliament , British Defence Minister Luke Pollard stated: "The budget for the Astraea project is estimated at around £15 billion during the current parliamentary term ."

The Mk4A nuclear warhead is currently being deployed by the UK on Trident II D5 missiles.

However, a portion of this budget is also being used to maintain the existing Mk4A warheads and modernize infrastructure at the UK Ministry of Defence's Atomic Weapons Development Facility (AWE).

Mr. Pollard emphasized that the UK Ministry of Defence would not publicly disclose the projected cost of Astraea "in order to ensure national security."

The Astraea project, designated A21/Mk7, is being designed, developed, and manufactured in the UK by AWE.

Astraea will replace the Holbrook warhead currently used on the Trident II D5 missiles equipped on Vanguard-class submarines and their Dreadnought-class successors.

This system was developed in conjunction with the U.S. W93 program, sharing some non-nuclear components such as the Mk7 casing within established treaty frameworks, to ensure continued compatibility with the Trident system.

The Trident II D5 missile, carrying six nuclear warheads, is currently in service with the British Royal Navy.

The UK's Defence Strategy Review 2025 report states that the sovereign warhead program will create jobs for approximately 9,000 workers in the defense nuclear sector. Astraea is expected to be commissioned in the 2030s, when the Holbrook warhead reaches the end of its operational lifespan.

According to official documents, Astraea will incorporate improved safety and performance measures, including hard-to-detonate explosives and technologies developed through the UK-US Joint Technology Demonstration program.

According to estimates by the Stockholm International Peace Research Institute (SIPRI), the UK currently possesses approximately 225 nuclear warheads, ranking ninth among nuclear-armed nations.

If the development of this nuclear warhead is complete, Britain can deploy it directly into service without actual testing. This is because the United Kingdom is currently a signatory to the Comprehensive Nuclear Test Ban Treaty.