UK to expand submarine fleet as defence review calls for 'warfighting readiness'

Monday's Strategic Defence Review will call for Britain's armed forces to move to a state of "warfighting readiness", spelling out changing security threats and which defence technologies are needed to counter them.

Britain will increase the size of its nuclear-powered attack submarine fleet, the government has announced ahead of a defence review expected to say the country must invest billions to be ready and equipped to fight a modern war.

Prime Minister Keir Starmer, like other leaders across Europe, is racing to rebuild his country's defence capabilities after U.S. President Donald Trump told the continent it needed to take more responsibility for its own security.

Monday's Strategic Defence Review will call for Britain's armed forces to move to a state of "warfighting readiness", spelling out changing security threats and which defence technologies are needed to counter them.

"We know that threats are increasing and we must act decisively to face down Russian aggression," defence minister John Healey said in a statement.

Britain will build up to 12 of its next-generation attack submarines, which are nuclear-powered but carry conventional non-nuclear weapons, to replace the current fleet of seven from the late 2030s, the Ministry of Defence said in a statement.

Britain operates a separate fleet of submarines armed with nuclear weapons. The government for the first time said a pre-existing programme to develop a new nuclear warhead to replace the model used by that fleet would cost 15 billion pounds.

"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," Healey added.

The new submarines will be a model jointly developed by the UK, U.S. and Australia under the security partnership known as AUKUS.

REVERSE DECLINE

In light of Trump's decision to upend decades of strategic reliance on the U.S. by Europe, Starmer has already committed to increasing Britain's defence spending in an attempt to reverse a long-term decline in its military capability.

He has promised to raise defence spending to 2.5% of GDP by 2027 and target a 3% level over the longer term. On Sunday he warned Britain must be ready to fight and win a war against states with advanced military forces.

In the days running up to the Strategic Defence Review, which Starmer commissioned shortly after taking office last July, the government has announced plans to spend billions on munitions plants, battlefield technology and military housing.

Juggling severely strained public finances, a slow-growing economy and declining popularity among an increasingly dissatisfied electorate, Starmer has sought to cast increased spending on defence as a way to create jobs and wealth.

"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," he is expected to say in a speech launching Monday's review.