UK to build up to 12 attack submarines as part of AUKUS program

The UK government has unveiled a major expansion of its defense capabilities, including plans to build up to 12 new conventionally armed, nuclear-powered submarines as part of the SSN-AUKUS program.

The new submarines will form part of a broader effort under the government’s Strategic Defence Review, which aims to transition the UK’s armed forces towards warfighting readiness in response to growing global threats.

The Strategic Defence Review, which is externally led, is expected to deliver 62 recommendations. The government is set to accept all of them. In response, ministers will commit to a landmark strengthening of the UK’s deterrence and defense strategy, with a particular focus on security in the Euro-Atlantic region.

As part of the plan, the government will increase stockpiles of munitions and essential support equipment, ensuring that industrial capacity can rapidly scale during crises. It will also procure up to 7,000 domestically built long-range weapons for the armed forces, supporting approximately 800 jobs in the defense sector.

A new CyberEM Command will be established to enhance the UK’s capabilities in cyber operations, backed by a £1 billion investment in digital defence infrastructure.

In addition, more than £1.5 billion will be allocated to repair and upgrade housing for military personnel and their families.

The defense overhaul follows a separate £15 billion investment in the UK’s nuclear warhead program and is a central part of the government’s broader Plan for Change, aimed at delivering national security while supporting economic growth and job creation.

Alongside the commitment to expand the UK’s conventionally armed attack submarine fleet, the government is securing the future of the Royal Navy’s Continuous At Sea Nuclear Deterrent, backed by a £15 billion investment into the sovereign warhead program.

“National security is the foundation of my Plan for Change, and this plan will ensure Britain is secure at home and strong abroad, while delivering a defence dividend of well-paid jobs up and down the country,” Prime Minister Keir Starmer is due to say.

“This Strategic Defence Review will ensure the UK rises to the challenge and our Armed Forces have the equipment they need that keeps us safe at home while driving greater opportunity for our engineers, shipbuilders and technicians of the future.”

This is the first time the UK has outlined the full scale of its investment plans in its warhead program. This will see significant modernization of infrastructure at the Atomic Weapons Establishment (AWE) in Aldermaston, according to the officials.

“With new state-of-the-art submarines patrolling international waters and our own nuclear warhead programme on British shores, we are making Britain secure at home and strong abroad, while delivering on our Plan for Change with 30,000 highly-skilled jobs across the country,” Defense Secretary John Healey said.

Currently, the UK is set to operate seven Astute-class attack submarines, which will be replaced with an increased fleet of up to 12 SSN-AUKUS submarines from the late 2030s.

Five Astute-class submarines, Anson , Astute, Ambush, Artful , and Audacious , are already in service, while the sixth vessel, HMS Agamemnon, was launched last October. The seventh unit will bear the name HMS Achilles.

UK’s seventh Astute-class submarine to be named HMS Achilles Vessels The boost to the SSN-AUKUS program will see a major expansion of industrial capability at Barrow and Raynesway, Derby, with the build of a new submarine every 18 months in the future.

The increase in capacity at the two sites will allow the UK to increase its fleet to up to 12 attack boats, as part of the AUKUS partnership.