The prime minister has denied authorising attacks on his ministers following reports his Health Secretary Wes Streeting was planning to oust him.
Speaking at Prime Minister's Questions on Wednesday, Sir Keir Starmer said: "I've never authorised attacks on cabinet members.
"I appointed them to their post because they're the best people to carry out their jobs."
The statement comes after some his allies told multiple media outlets he could face a leadership challenge from Mr Streeting.
The health secretary has denied he was lining up a leadership bid, and called on those behind the briefings to be sacked.
Starmer said the briefings were "unacceptable", and defended Streeting saying "the health secretary is getting on with his job and doing a very good job."
Conservative leader Kemi Badenoch said Starmer's government has "descended into civil war",
She told MPs: “He says these attacks aren’t authorised, that means he’s lost control of Number 10, because that’s where they’re coming from."