Labour figures criticise calls for inquiry into PM's Mandelson claims

He added that this did not affect his decision to give Lord Mandelson security clearance to take up the role.

In an apparent effort to clarify his comments in Parliament, Sir Keir told the Sunday Times there are "different types of pressure".

"There's pressure – 'Can we get this done quickly?' – which is not an unusual pressure. That is the everyday pressure of government," he said.

Defending the prime minister, Environment Secretary Emma Reynolds said: "It was categorically proven last week that the PM did not lie to Parliament.

"The prime minister had said that due process was followed and due process was followed, unfortunately the process was fundamentally flawed."

A vote on launching a Privileges Committee inquiry is likely to take place on Tuesday - the same day that senior former government figures are due to give evidence to the Foreign Affairs Committee including the prime minister's former chief of staff Morgan McSweeney and former senior civil servant at the Foreign Office Sir Philip Barton.

Liberal Democrat leader Sir Ed Davey said: "Labour MPs must be given a free vote on any motion to refer Starmer to the Privileges Committee, not forced into being accomplices to a cover-up.

"If Keir Starmer has misled the House and the public, he must be held to the same standard that we should expect of any prime minister."

Reform UK's economic spokesman Robert Jenrick said the prime minister had "misled Parliament" and had "behaved appallingly".

However, he added: "Parliament needs to actually talk about the priorities of the British people, and that is not primarily about the ins and outs of Peter Mandelson."

In a joint statement to the Times, former Labour ministers Johnson and Lord Blunkett said the Conservative calls for a Privileges Committee inquiry were a "nakedly political stunt".

"Any comparison with Boris Johnson is absurd. When Parliament referred that matter to the Privileges Committee, a police investigation had directly disproved his categoric statements that he knew nothing about the breach of lockdown rules," they said.

Speaking to the BBC Radio 4's Today programme, Dame Emily Thornberry said her committee was investigating the appointment and that she did not want the Privileges Committee to be "duplicating the work we're doing".

"It may be that at some stage in the future, some of the questions haven't been answered, and it is decided that they are of sufficient importance that the Privileges Committee should be involved," she said.

"But I don't really see why we're doing it at the moment, apart from, potentially people trying to score points in advance of the local elections.

"I'm sorry to say that, and I'm not supposed to be partisan on this, but it is as plain as the nose on my face what's going on here."

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