Angela Rayner is said to be preparing a bid to oust Sir Keir Starmer as Labour leader.
On Thursday, Labour MPs came out of the woodwork to push both Ms Rayner and Wes Streeting to launch a leadership challenge against Sir Keir over the Lord Mandelson scandal.
The ex-Deputy PM is now said to have put together a £1million-valued war chest to back her bid - just days after leading a Labour revolt against attempts to "cover up" files around Lord Mandelson's chaos-ridden appointment as US ambassador.
She has also told friends she is "ready" to launch a leadership campaign, according to the Mail.
But Ms Rayner's rumoured ambitions could be derailed by over an unresolved investigation into her tax affairs - for which she resigned last year.
Labour MPs, including her own allies, have warned they may not back her while an HMRC probe runs on.
"I worry about the outstanding tax she apparently owes," one on the party's left told The Telegraph.
Another MP said: "She could win the members. However, I don't see how she can be a candidate until she's paid. A lot of the wider party would love her to stand."
Last night, the Prime Minister hosted Labour MPs at Chequers in a bid to win them over after a week of party turmoil.
But his party's heavyweights have publicly laid into him - ex-frontbencher Andy McDonald said his job was "hanging by a thread".
Labour's former deputy leader Baroness Harman said Sir Keir looked weak and gullible, warning on Sky News's Electoral Dysfunction podcast that the scandal would "finish" him.
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Labour MP calls for Morgan McSweeney to leave No10: 'There’s a lot of anger!'
A Labour MP has called for Sir Keir Starmer's Chief of Staff, Morgan McSweeney, to leave Downing Street after the Peter Mandelson scandal.
Yesterday, the Prime Minister apologised for believing Lord Mandelson's "lies" and appointing him as the UK's ambassador to the US.
Simon Opher, MP for Stroud, this morning called for a "clearout" at No10, including Mr McSweeney.
"There’s a lot of anger amongst Labour MPs, because really we want to, I mean, yesterday, I want to be talking about the cancer care plan, not about Peter Mandelson," Mr Opher told the BBC.
"So I think what we need to do, I think what needs to really happen, Keir Starmer needs to change his advisers in No10, I think he’s been badly advised, and he’s been really let down, particularly on this decision.
"I know in politics, we really rely on people to sort of cover our backs, our advisors, and I think they patently haven’t done this with Peter Mandelson, and I think so we need a bit of a clear out really at No10."
When pressed whether this meant Mr McSweeney leaving, Mr Opher replied: "I think so yes".
"If my chief of staff had done this I think he would be looking for another job to be honest," he added.
In the capital... Sadiq Khan REFUSES to back bus driver sacked after stopping thief
Sir Sadiq Khan has been urged to break his silence and back the bus driver who was sacked after stopping a thief.
The London Assembly passed a unanimous motion yesterday praising Mark Hehir - who was sacked in 2024 after knocking out a man who stole a passenger’s necklace.
While the motion is non-binding, it piles pressure on the London Mayor - who is yet to comment on the case.
The leader of the Conservatives in the London Assembly, Susan Hall, has supported Mr Hehir and met him during his visit to Parliament this week.
Mr Hehir said: "I want to thank Susan and the whole Assembly for supporting me. To have everyone come together, all different parties, it means a lot.
“I hope the Mayor now finally says something, as it’s disappointing he hasn’t so far. I would welcome the chance to speak with him about it. I hope he will give his support as well.”
Wes Streeting quietly deletes images of Lord Mandelson from social media - including one with his MOTHER
Wes Streeting has quietly removed a number of images of himself and his family with disgraced Labour grandee Lord Mandelson - including this one
|X/WESSTREETING
Wes Streeting has quietly removed a number of images of himself and his family with disgraced Labour grandee Lord Mandelson.
One was published just one day after Mr Streeting first became a Labour MP in Ilford North in May 2015 - a seat he now holds by a hair's breadth against his pro-Gaza independent challengers.
Lord Mandelson, who was then running his public affairs firm Global Counsel, had campaigned in the constituency for Mr Streeting.
"Oh, look it's my mum's new mate Peter Mandelson on the telly," the now-Health Secretary said of the photo at the time. "Mum, a big lefty, loved him today."
Team Rayner hits back amid reports ex-Deputy PM is plotting bid to oust Keir Starmer
A spokesman for Angela Rayner has hit back at reports of a leadership bid
|PA
A spokesman for Ms Rayner hit back at reports in the Mail and Telegraph of a leadership bid late last night.
He hit back at suggestions that she told friends she was ready to run, saying: "We do not recognise these claims".
Then, turning to question marks over her tax affairs, a spokesman said: "Angela said she would cooperate fully with HMRC and continues to do so. A running commentary is not helpful."
RECAP: Voters demand Keir Starmer quits as PM after Lord Mandelson scandal puts premiership on the brink
Half of Britons want Sir Keir Starmer to quit as Prime Minister following shock revelations about Lord Mandelson, a bombshell poll has revealed.
The survey, conducted by YouGov, found that just 24 per cent of voters want Sir Keir to stay as Labour leader and Prime Minister.
Labour voters remain split on whether Sir Keir should stay in No10, with just 40 per cent supporting the Prime Minister and 37 per cent wanting new leadership.
Meanwhile, an overwhelming majority of both 2024 Tory and Reform UK voters back Sir Keir stepping down.
YouGov polled 6,741 Britons about Sir Keir on February 5, just hours after the Prime Minister admitted No10 knew Lord Mandelson visited Jeffrey Epstein's house before appointing him as the UK's Ambassador to the US...
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