The prime minister faces a standards investigation over Mandelson affair and testimony from Morgan McSweeney

Keir Starmer has told Labour MPs to “stick together and fight together” as ministers launched a massive operation to shore up his fragile position before a critical day for his premiership.

The prime minister faces the double threat of a standards investigation into his decision to appoint Peter Mandelson as ambassador to the US and a potentially damaging testimony from Morgan McSweeney, his former chief of staff.

Commons speaker grants application by Tories for vote on investigation into whether PM misled MPs, say sources

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Keir Starmer will face a vote on whether to launch a standards investigation into his decision to appoint Peter Mandelson as ambassador to Washington.

The speaker, Lindsay Hoyle, has granted a debate on Tuesday on potentially referring the prime minister to the privileges committee over claims he misled the Commons.