The United Kingdom says it will build as many as 12 attack submarines to replace its current fleet of seven Astute-class boats.
The government’s call for new submarines is included as part of its Strategic Defence Review (SDR) released in June 2025. The next-generation submarines will be produced as part of its AUKUS partnership with Australia and the United States, according to Reuters. The submarines will be nuclear-powered but carry conventional weapons, said the Ministry of Defence, which wants the boats in service by the late 2030s.
“When we are being directly threatened by states with advanced military forces, the most effective way to deter them is to be ready, and frankly show them that we’re ready to deliver peace through strength,” British Prime Minister Keir Starmer told workers at BAE Systems’ Govan shipbuilding site in Scotland, according to Reuters.
The 62 recommendations in the wide-ranging SDR update the U.K.’s defense approach to addressing threats from Russia, nuclear risks and cyberattacks, according to Reuters. A Bloomberg analysis of the document, which included some $20 billion for new nuclear warheads, called it “explicit in the need for Britain to play a greater role in nuclear deterrence, as the only European country to assign its nuclear capability” to NATO defense.
“We know that threats are increasing, and we must act decisively to face down Russian aggression,” British Defence Minister John Healey said in a statement.
The SDR also calls for the U.K. to invest more in drones and digital warfare rather than relying on a larger Army. Under it, the U.K. will also build at least six new munitions plants, procure up to 7,000 British-made long-range weapons, and create a Cyber and Electromagnetic Command which will lead defensive and offensive cyber capabilities, according to Reuters.
The government accepted all the recommendations in the SDR, including the building of submarines, the BBC reported. “With new state-of-the-art submarines patrolling international waters and our own nuclear warhead program on British shores, we are making Britain secure at home and strong abroad,” Healey said in the statement.
In the wake of U.S. calls for NATO members to increase defense spending, Starmer pledged to increase spending. Officials devised the SDR with an increase in defense spending in mind — especially the submarine commitment, which would require an increase to at least 3%, the BBC reported.
The SDR also envisions the Royal Navy moving toward a “more powerful but cheaper and simpler fleet,” and the U.K.’s two aircraft carriers, which are the largest in Europe, shifting to use as a base for European — rather than only British — aircraft and drones, according to CNN. “The moment has arrived,” Starmer said, “to transform how we defend ourselves.”