Defence secretary John Healey has pledged that the UK will spend 3 per cent of GDP on defence by 2034, in the wake of demands from Donald Trump.
The government previously set out its “ambition to reach 3 per cent in the next parliament”, after it rises to 2.5 per cent within the next two years.
But Mr Healy has promised a “certain decade of rising defence spending” and said there was “no doubt” the UK would meet its target, in an interview with The Times.
Mr Healey told the newspaper: “It allows us to plan for the long term. It allows us to deal with the pressures.”
His comments come amid persistent pressure from President Trump, who has urged Nato allies to raise defence spending to 5 per cent of GDP – more than double the alliance’s current 2 per cent target.
Ministers are preparing to unveil a new defence review this week, which is expected to warn of an "immediate and pressing" threat by Russia and draw heavily on the lessons learned from the war in Ukraine.
It is thought cyber experts will also be sent to the front line alongside regular forces in a move designed to modernise the British military.
Ministers have already announced they are to spend an additional £1.5 billion fixing up military houses amid claims years of neglect has led to troops quitting.
The pledge on funding could prove controversial. Money to meet the 2.5% target was found by slashing overseas aid from 0.5 per cent to 0.3 per cent of GDP, a move which prompted then-international development minister Anneliese Dodds to resign.
At the time told Sir Keir Starmer: “You have maintained that you want to continue support for Gaza, Sudan and Ukraine; for vaccination; for climate; and for rules-based systems.
“Yet it will be impossible to maintain these priorities given the depth of the cut.”
When he announced the targets earlier this year, the prime minister said: “In an ever more dangerous world, increasing the resilience of our country so we can protect the British people, resist future shocks and bolster British interests, is vital.”
Nato heads of government are set to meet in The Hague, in the Netherlands, next month.
Addressing the alliance’s parliamentary assembly in Dayton, USA this month, Nato secretary-general Mark Rutte said: “I assume that in The Hague we will agree on a high defence spend target of, in total, 5 per cent.”
A Ministry of Defence spokesperson said: “This government has announced the largest sustained increase to defence spending since the end of the Cold War – 2.5 per cent by 2027 and 3 per cent in the next parliament when fiscal and economic conditions allow, including an extra £5 billion this financial year.
“The strategic defence review will rightly set the vision for how that uplift will be spent, including new capabilities to put us at the leading edge of innovation in Nato, investment in our people and making defence an engine for growth across the UK – making Britain more secure at home and strong abroad.”
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