Chaos at the heart of Government has left senior Labour figures worried a “zombie” Prime Minister will lead the party into an election disaster. Senior ministers pledged their loyalty to Sir Keir Starmer as he came under fire for his appointment of Peter Mandelson as US ambassador but there are fears he is now a “prisoner of the cabinet” and too weak to stage a reshuffle or push forward urgent but controversial reforms to welfare.

A former high-ranking Labour figure said: “I don’t think he can turn things round. I think he is completely useless as a leader. People keep saying he is a decent bloke and all the rest of it, but I think his backbenchers know they can control him and as a consequence he can’t seem to set out a programme of action and then stick to it."

A Labour MP was reminded of the Conservatives under John Major in the run-up to the 1997 election and the last chapter of Gordon Brown’s premiership, with the party led by an unpopular leader, unable to unite around a successor and heading towards loss of power.

The MP said: “A zombie prime minister ambled into a general election which he lost.”

Predicting that Chancellor Rachel Reeves will stay in place, the source said: “I think any controversial reforms are now completely off the agenda. I think Rachel is extremely safe, as is David Lammy. He is a prisoner of the cabinet.”

There has been strong speculation Sir Keir will go in the wake of the May elections, when Labour is expected to lose control of the Welsh Government for the first time and take a drubbing in council contests.

But the MP doubted the party could come together around an alternative, saying: “Wes Streeting is probably now going to find it nigh-on impossible to even stand for the leadership. His relationship with Mandelson probably has ended any hopes of that in the near future… If Starmer won’t resign we’re stuck with him then until the general election.”

A former Labour minister was appalled by the collapse of confidence in MPs’ ranks and the open divisions between different parts of the party – with Scottish Labour leader Anas Sarwar openly calling for Sir Keir to go.

He said: “One of the things that’s really appalled me is the cowardice of so many in the Labour party who have just assumed they are going to lose when there are three years left before the next election. One would have thought they would have concentrated instead on delivering for the country and not being so paranoid about the results, whether of by-elections or national elections in Wales and Scotland.

“That’s not the way to conduct yourself as an elected representative. You’ve got to show people leadership and confidence and that’s sadly absent, I’m afraid, in so many MPs now. They appear to be worried only about their own seats.”

Warning the Welsh and Scottish wings of Labour against trying to distance themselves from the Westminster party, he said: “In my experience, divided parties – whether it’s along national lines or regional lines – always result in defeat. Always.”

Pollsters Opinium this month found Sir Keir’s net approval ratings are “lowest on whether he is in touch with ordinary people” with a score of minus 44.

However, four in 10 did not believe that Kemi Badenoch looked like a Prime Minister in waiting, compared with 23% who said she did.

More than half (52%) of the public said the UK Government is doing a bad job at handling relations with Donald Trump, compared to just 28% who said it is doing a good job.

James Crouch, head of policy and public affairs at Opinium said: “Keir Starmer has been on net minus 40 or below for approaching a third of his premiership. The sustained nature of these low approval ratings is what drives the leadership speculation with every passing crisis.”