Scottish Labour leader Anas Sarwar is to call for Sir Keir Starmer to step down as prime minister, Sky News understands.

Mr Sarwar has called an unscheduled news conference at 2.30pm, when he will suggest the prime minister should step down.

He will be the most senior Labour voice to call for Sir Keir to go after several backbenchers have done so following more revelations about Lord Mandelson’s links to paedophile Jeffrey Epstein.

Sir Keir’s leadership looks to be in freefall after his chief of staff, Morgan McSweeney – his right-hand man – resigned on Sunday over his role in appointing Lord Mandelson as ambassador to the US.

Tim Allan, his director of communications, then quit on Monday morning, saying he wants to “allow a new No 10 team to be built”.

However, Sir Keir’s spokesman insisted he was “upbeat and confident” and would not be resigning today.

Mr Sarwar, who is from the same wing of Labour as the PM, has so far remained quiet about his feelings on how the government is working in Westminster, but as the Holyrood elections approach in May, he appears to want to distance himself from his party’s leader.

His unexpected intervention will come just hours before Sir Keir addresses his MPs at a Parliamentary Labour Party meeting in Westminster on Monday evening.

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