The renewed speculation over Starmer’s position will likely be the focus of gilt traders on Monday morning. Investors have in the past reacted negatively to the prospects of Starmer or Chancellor of the Exchequer Rachel Reeves leaving their posts, out of concern they could be replaced by colleagues less committed to fiscal rigor.

“It’s not good for the country to change its prime minister every 18 months or two years,” McFadden told Sky News on Sunday. “It’s leading to chaos and uncertainty economically, politically and reputationally around the world.”

Even if Starmer survives the clamor for accountability around Mandelson, he faces jeopardy in the coming weeks. The most imminent flashpoint is a Feb. 26 special election in Gorton and Denton, a constituency which ought to be a Labour stronghold but where the Greens and Reform UK are now vying for first place. Just over two months later follows a wider set of local elections where polls suggest Labour will hemorrhage seats.

After losing his second chief of staff in just 19 months, Starmer moved swiftly to promote McSweeney’s former deputies, Jill Cuthbertson and Vidhya Alakeson to jointly fill the vacated role. His office indicated the prime minister is likely to make an intervention on Monday to update the country on his next steps to deliver the change promised by his party in 2024.

He has voiced frustration in recent days over how the Mandelson crisis is distracting from that agenda. The latest ructions were sparked by revelations that the former member of the House of Lords appeared to have leaked sensitive government information to Epstein while serving as a minister more than 15 years ago.

That put fresh scrutiny on Starmer’s judgment in appointing someone who’d twice resigned from government in controversial circumstances and was nicknamed the Prince of Darkness because of his mastery of political manipulation.

One previously loyal supporter of Starmer said they expected him to now be forced out. Last year’s welfare-policy U-turn had been the beginning of the end for the premier by displaying his weak command of his party and lack of conviction in his own project, they said. Another erstwhile Starmer supporter said Labour had let the country down by behaving no better than the Tories they replaced, despite campaigning to restore decency to politics.

Critics were circling on Sunday when two key Labour-linked groups suggested responsibility for Mandelson’s appointment shouldn’t end with the chief of staff.

Mainstream, a network of left-leaning Labour politicians, said: “All those involved” in Mandelson’s appointment “must be held to account.” Compass, another left-wing pressure group, was blunter: “in time, a new captain will be needed to steer the party.”

Opposition parties also wasted no time in turning the focus on Starmer. “The buck stops with him,” said Deputy Leader of the Liberal Democrats Daisy Cooper, while main opposition Conservative Party Leader Kemi Badenoch said on X that Starmer should “take responsibility for his own terrible decisions.” Nigel Farage, the populist leader of the poll-leading Reform UK Party, predicted that the premier “won’t be far behind” McSweeney.

In the House of Commons the displeasure from Labour’s own ranks was on display this week when the party’s backbenchers — led by Rayner — opposed government efforts to water down a Tory motion seeking the disclosure of documents relating to Mandelson’s appointment and tenure as ambassador. The rebels got their way, and the government is now preparing to disclose thousands of pages of information, though no date has yet been set for publication.

Rayner is now seen as the front-runner to become premier, but Labour figures tipped at least six others to go for the job, including Miliband, Streeting, Home Secretary Shabana Mahmood and Foreign Secretary Yvette Cooper. Several people on the Labour right suggested Defense Secretary John Healey should take over.

–With assistance from Shiyin Chen and Valentine Baldassari.

(Corrects spelling of the Gorton and Denton constituency.)

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