PRIME Minister Sir Keir Starmer’s government was locked in a death spiral day as Scottish Labour leader Anas Sarwar led growing calls for the premier to quit while another top aide fled Downing Street.

In an atmosphere redolent of the last days of Liz Truss, Labour MPs were predicting the end for Sir Keir’s tenure in office was nigh, even as the beleaguered Prime Minister insisted he was going to carry on.

Sir Keir’s position is in jeopardy over his decision to appoint Peter Mandelson as ambassador to the US despite his friendship with paedophile financier Jeffrey Epstein.

Mr Sarwar was the first crack in the leadership dam, but cabinet ministers were loud in their initial silence, until ordered to get tweeting mid-afternoon in support of their boss.

Just a day after his top adviser and factional mastermind Morgan McSweeney was forced to resign, Sir Keir lost communications chief Tim Allan, a New Labour-era retread, who tersely announced his departure.

The fourth holder of the post to depart in Sir Keir’s 18 months in office, it is clear that the job of burnishing the government’s image is defeating the most experienced professionals.

“I have decided to stand down to allow a new No 10 team to be built. I wish the PM and his team every success,” was all he communicated by way of explanation.

Mr Sarwar, who Sir Keir once boasted of helping into position by pushing out former Scottish Labour leader Richard Leonard, has now joined the chorus of calls for his resignation both inside Scottish Labour by Brian Leishman MP, and from SNP Westminster leader Stephen Flynn.

The Scottish Labour leader hit out at “failures in the heart of Downing Street,” warning they were hurting Labour’s chances in Scotland.

He is the most senior Labour politician to call for Sir Keir to go, with Scottish Labour facing the prospect of a fight with Reform for a distant second to the SNP in May’s Holyrood elections.

Mr Sarwar, who once described Mandelson as “an old friend,” turned to the fate of his “friend” in No 10, saying: “The distraction needs to end and the leadership in Downing Street has to change.

“Does this cause me personal hurt and pain? Of course it does.

“We have an SNP government that is addicted to secrecy and cover ups with devastating consequences.

“That’s why I have to be honest about failure wherever I see it.

“The situation in Downing Street is not good enough. There have been too many mistakes.

“Have there been good things? Of course, there have, many of them, but no-one knows them and no-one can hear them because they’re being drowned out.

“That’s why it cannot continue.”

Scottish Green co-leader Gillian Mackay branded it a “devastating day for Labour when even Anas Sarwar agrees that the Prime Minister cannot be trusted.”

She posed the question: “How can he ask people to support a Labour Party that is led by a man who even he thinks is unfit for office?”

Sir Keir was scheduled to address Labour MPs last night in a last-ditch attempt to save his premiership.

Earlier he told remaining Downing Street staff that he had been “absolutely clear that I regret the decision that I made to appoint Peter Mandelson” as ambassador to the US — a decision Mr McSweeney took the blame for in his resignation on Sunday.

“And I’ve apologised to the victims which is the right thing to do,” he added.

He went on to lavish praise on the absent Mr McSweeney and to promote the government’s achievements: “In just a few months, we start the work of lifting half a million children out of poverty.

“A massive thing to do in this country because that means that lives will be changed.

“We must prove that politics can be a force for good. I believe it can. I believe it is.

“We go forward from here. We go with confidence as we continue changing the country.”

Labour politicians across the party were very much more sceptical.

Left MP Andy McDonald warned that if the premier “doesn’t own the error he’s made, and recognise the problem in front of it and articulate it and tell us how he’s going to deal with it, then I’m afraid it is coming to an end — if not today, but certainly in the weeks and months ahead.”

He accused Sir Keir of promoting “no change other than to purge the left, and it’s got us in this terrible mess that we’re in now.”

Mr McDonald said he wanted to see a change to a “more pluralist, democratic socialist agenda.”

And Graham Stringer, on the right of the party, dismissed suggestions that Sir Keir could hang on.

He said: “When I come into the House of Commons and talk to everybody, I don’t hear that opinion at all. So it is clearly a question of when, not if.”

Green Party leader Zack Polanski said: “McSweeney needed to go, but so too does Starmer.

“This whole saga also demonstrates how broken and compromised our politics is and that Labour can’t and won’t fix it.

“We need a different kind of politics — one where powerful, wealthy and corrupt men are shown the door, where exploitation is rooted out and inequality tackled.”

With Labour trembling on the brink of a contested leadership election while in office, something that has not happened since 1976, internal divisions are coming to the fore.

Left MP Brian Leishman, called for Sir Keir to go and accused Mr McSweeney of creating “factionalism” in Labour ranks.

He said: “McSweeney was at the heart of the political mistakes made since the general election. He helped create this factionalism in the Labour Party.

“The Prime Minister must consider following McSweeney’s lead one last time and doing the same.”

This was met by David Taylor MP, one of Mr McSweeney’s faction, with a suggestion that Mr Leishman did nothing but “criticise. Perhaps you’d be better off in Your Party.”

Against this background, most eyes are fixed on former deputy premier Angela Rayner and Health Secretary Wes Streeting as likely successors, with the latter tainted by his close friendship with Mr Mandelson, who is presently under police investigation.