Pressure is ramping up on Sir Keir Starmer once more following the resignation of Defence Secretary John Healey and armed forces minister Al Carns.
Healey quit the government on Thursday in spectacular fashion with a scathing letter warning that defence spending restraints meant he was being "forced" to make decisions that "could make the country less safe".
In his resignation letter to Starmer, Healey wrote: "You have been unable, and the Treasury has been unwilling, to commit the resources that the nation needs to defend the country at this time of rising threats."
He went on: "You spelled out the threats last week: 'it is our intelligence assessment, and the assessment of other countries in NATO, that there could be an attack by Russia on NATO as soon as 2030.'
"You know what defence needs. You made the argument for this powerfully in your speech at the Munich Security Conference back in February. Without a DIP [Defence Investment Plan] that meets the moment in this way, I am being forced to make decisions that would reduce the readiness of our Forces and increase the risk to personnel on operations, and could make the country less safe.
"After explaining to you that I would not be able to accept a DIP settlement that does not give our Forces the resources they need, I am now left with no other option than to submit my resignation as your Defence Secretary."
Healey's resignation was followed hours later by armed forces minister Al Carns' and those of two parliamentary private secretaries in the Ministry of Defence.
In the wake of Healey's resignation, former Security Minister Dan Jarvis has been appointed the new Defence Secretary.
Starmer said: “My first duty is to keep the British people safe, and I will always do what is necessary to protect our national security.
“I am pleased to appoint Dan Jarvis as Defence Secretary as we strengthen our armed forces and meet the growing threats facing our country.
“This Labour Government is delivering the largest sustained increase in defence spending since the Cold War.
“In a dangerous and volatile world, we will give our armed forces the capabilities they need to defend Britain and keep our nation secure.”