Sir Keir Starmer has apologised to his health secretary after allies of the prime minister accused him of plotting a coup.
Sky News understands Sir Keir spoke briefly to Wes Streeting on Wednesday evening, though did not share details about the briefing campaign.
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Speaking at Prime Minister's Questions earlier in the day, he denied authorising the attacks on Mr Streeting, who was accused of planning a leadership challenge after the budget later this month.
Mr Streeting said the allegations are "not true", telling Sky News' Mornings With Ridge And Frost that whoever was behind the briefings had been "watching too much Celebrity Traitors".
He insisted he was loyal to the prime minister, who has been under mounting pressure as he and the Labour Party flounder behind Reform in the polls.
Downing Street went on the attack on Tuesday night to ward off any potential challenge to Sir Keir after the budget, which could see the government announce manifesto-breaking tax rises.
Sir Keir and Rachel Reeves have refused to rule out raising income tax, national insurance, or VAT.
One senior figure told Sky News political editor Beth Rigby while a post-budget challenge is unlikely, it could come if next May's elections - including in London and Wales - go badly for Labour.
Labour face a challenge from Reform on the right and parties like the Greens and Plaid Cymru on the left.
Read more: How No 10 plunged itself into crisis
Also under pressure is the prime minister's chief of staff, Morgan McSweeney, after Mr Streeting hit out at a "toxic culture" inside Number 10.
Sir Keir failed to say he had "full confidence" in him at PMQs in response to questions from Kemi Badenoch, but the prime minister's political spokesperson later insisted to journalists that he does retain his backing.
Sky News understands Mr McSweeney was not discussed when Sir Keir and Mr Streeting spoke last night.
Labour chairwoman Anna Turley said the prime minister will investigate the source of the claims against the health secretary, telling ITV: "This is not what he wants to see and he's determined to drive it out."
(c) Sky News 2025: PM apologises to health secretary over coup accusations
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