Angela Rayner has repeatedly threatened to quit the Government over Labour’s “impossible” pledge to build 1.5 million homes over the course of this parliament. A new tell-all biography by Lord Ashcroft reveals that the Deputy Prime Minister and deputy Labour leader was only persuaded out of resigning thanks to a last-minute intervention by Tony Blair.

Ms Rayner is said to believe Labour’s housebuilding policy is never going to be achieved, and shouldn’t have been promised to voters last year. The deputy PM is also said to be angered by losing out on Dorneywood, the 21-room grace-and-favour mansion in Buckinghamshire, to Rachel Reeves. While Tony Blair gave use of the home, and its 215 acres of parkland and woodland, to his deputy Prime Minister John Prescott, Sir Keir kept with recent Tory tradition of handing it to his Chancellor.

Eventually Ms Rayner was handed an apartment in Admiralty House on Whitehall, after attempts to “fob her off with a property in Northern Ireland”.

Lord Ashcroft’s updated biography of the Prime Minister, Red Flag, claims that ms Rayner “threatened to resign because she felt she'd been set the impossible target of Labour building 1.5 million new homes.”

“It took a call from Tony Blair to talk her down – which, incidentally, tells you how important Blair is to the Starmer project.”

A Labour source warned that Ms Rayner’s housebuilding programme will inevitably unwind, as Britain doesn’t “have enough bricks and there isn't enough water to supply these houses”.

A Labour MP added: “I think Rayner realised a while ago that the 1.5million new homes target is undeliverable.”

"But now the penny's dropped for Angie's team that she was set up to fail on this all along.”

However former Labour MP Jonathan Ashworth said he will “eat my hat if Angela Rayner quits the Cabinet”.

The former frontbencher added: “I’m a big fan of Angela Rayner, I think she’s brilliant.”

A source close to Ms Rayner said: 'We do not recognise the claims made. Angela is proud to be serving as Deputy Prime Minister in Keir's cabinet and delivering on Labour's crystal clear commitment to build 1.5 million homes as part of our Plan for Change.”

Ms Rayner nearly launched a coup against Sir Keir in 2021 after she was sacked as chair of the Labour Party in a botched reshuffle.

According to a book documenting Sir Keir’s five years as leader of the opposition, the news of her sacking was greeted by Ms Rayner swearing at him before storming out of the meeting.

Sources claimed she was then ready to launch a coup against the leader, backed by the trade unions, before backing down to avoid “a nuclear missile on their faces”.