Keir Starmer is set to face questions from MPs after thousands of newly released documents exposed cracks in his government and raised questions over his use of disappearing messages.
The British prime minister’s weekly appearance in the Commons at Prime Minister’s Questions will be the first opportunity MPs have to grill him about the content of the latest files related to Peter Mandelson’s appointment as Britain’s ambassador to the United States.
Monday’s document dump revealed private messages between Mandelson and senior ministers in which they admitted their frustrations with Starmer’s leadership and the heart of government.
In one WhatsApp exchange between Mandelson and UK work and pensions secretary Pat McFadden, the senior minister complained every meeting he had was to discuss “who can we tax in order to pay benefits to others”.
Foreign secretary Yvette Cooper would not be drawn into saying whether she believed Starmer was a strong and effective leader, when asked by journalists about the messages revealed by the Mandelson files as she visited China.
Downing Street, meanwhile, revealed the limited number of written messages between the British prime minister and Mandelson contained in the files was because Starmer uses disappearing WhatsApp messages.
The disappearing messages function on WhatsApp means that Starmer’s communications with Mandelson on that platform have not been preserved.
The British prime minister defended his use of the function, telling broadcasters: “All the messages I hold have been passed over.
“I went through the same process as everybody else.
“And many people, not just in politics, use disappearing messages.”
Starmer, along with Cooper, sacked Mandelson in September 2025 after leaked emails which showed the peer sent supportive messages even as late paedophile financier Jeffrey Epstein faced jail for sex offences.
MPs voted earlier this year to force the disclosure of documents relating to his time as ambassador.
The Commons is set to debate the second tranche of the files on Wednesday afternoon, following Prime Minister’s Questions.