Sir Keir Starmer is reportedly set to overrule Rachel Reeves by calling for increased military spending in a bid to boost support for Ukraine.
The Prime Minister will scramble to Paris on Monday for emergency talks with European counterparts after the US heaped pressure on Europe to bolster its support for war-torn Ukraine.
It comes as David Lammy warned the Chancellor that defence spending may need to treble to Cold War levels if Russia is allowed to win in Ukraine.
Sir Keir is expected to overrule his Chancellor and call for increased defence spending in a bid to woo Donald Trump before he flies to Washington to meet the president at the White House.
Downing Street has maintained plans to boost defence spending since Labour entered power last year but has yet to give a timetable as to when they will reach their goal of 2.5% of GDP. The spending review will set out the roadmap for hitting this.
The UK is currently at 2.3% of spending – although there are calls to reach 2.65% of GDP.
The foreign secretary told the Munich Security Conference “Putin will not go away”, and that, while it was positive 23 Nato countries were now spending at least 2% of their GDP on defence, “we all know we have to go upward”.
He said the UK was “absolutely” committed to spending 2.5% and would set out a “pathway” to achieving that goal in a few months’ time.
Lammy’s comments come after US Vice-President JD Vance told the conference on Friday that Europe must “step up in a big way to provide for its own defence”.
