Keir Starmer is under increasing pressure to resign today amidst allegations that Lord Mandelson failed security vetting prior to his appointment as US ambassador, even though the Prime Minister claimed he had been cleared by intelligence agencies.

The architect of New Labour reportedly faced an initial denial of developed vetting clearance in January 2025, only weeks after the Prime Minister had officially announced his new role.

According to sources from the Guardian, the Foreign Office exercised an unusual authority to override the security officials’ recommendation.

Despite the government’s release of documents about the process, this denial of clearance for Mandelson had not come to light before now. It remains unclear if this decision was influenced by his connections to Jeffrey Epstein.

Sir Keir had previously assured that Mandelson underwent a thorough security vetting process, carried out independently by security services, which ultimately cleared him for the ambassadorial position.

Now, political parties including the Conservatives, Reform, the Liberal Democrats, and the Greens are all calling for Sir Keir’s resignation. Additionally, Labour MPs are pressing the Prime Minister for full transparency on the issue.

Tory leader Kemi Badenoch said: ‘If he has misled Parliament, as it looks like he has, he should resign. 

‘If he has broken the ministerial code, as it looks like he has, he should resign. If he withheld documents by a cover-up from Parliament, he should resign.’

Mandelson is said to have been initially denied clearance in January 2025 – weeks after the PM had officially announced his appointment 

Keir Starmer is facing a fresh Mandelson storm today amid claims the peer failed security vetting before becoming US ambassador

Tory leader Kemi Badenoch said Sir Keir ‘misled the House’ over Mandelson’s vetting process

Nigel Farage said the PM had ‘blatantly lied’ and should resign

A three-page ‘due diligence’ report supplied to Sir Keir on December 11, 2024 flagged the ties between Mandelson and Epstein

Nigel Farage said: ‘Now we discover that he has blatantly lied, the Prime Minister should resign.’ 

Lib Dem leader Ed Davey also called for the PM’s resignation. ‘Keir Starmer had already made a catastrophic error of judgement,’ he said. 

‘Now it looks as though he has also misled Parliament and lied to the British public. If that is the case, he must go.’ 

The claims risk reviving the furore that already came close to exploding Sir Keir’s premiership in February.

Labour MPs have been up in arms that Mandelson was given the key job despite long-standing ties to Epstein.

The Guardian cited multiple sources for the claim, and it is not known whether the PM was aware his pick for ambassador had not been approved by the UKSV agency.

It is understood Mandelson is adamant that he did not know he had been rejected until the reports today.  

It is also not clear who in the Foreign Office made the apparent decision to overrule UKSV. 

Olly Robbins is believed to have been the permanent secretary at the time, while Deputy PM David Lammy was Foreign Secretary. 

Tonight Foreign Affairs Committee chairwoman Emily Thornberry said she would summon Sir Olly to clarify information he gave it at a previous hearing.

‘Looking at the evidence that was given and the letters that have been written, to be charitable, there are glaring holes,’ she said.

‘It really is a question of whether we were knowingly misled.’ 

Developed vetting is standard for most mid-level diplomatic staff. An outright refusal of clearance is believed to be quite rare, although ‘mitigations’ can be requested.  

In another potentially incendiary claim, the Guardian said senior Government officials have been considering whether to withhold documents about the refusal from Parliament. 

Labour MPs rebelled to insist on the publication of a huge range of material about the process, and the cross-party Intelligence and Security Committee is meant to be having the final say on what is too sensitive for publication. 

The Daily Mail understands no document showing that vetting clearance was initially refused has been supplied to the ISC so far.

At an event in East Sussex on February 5, Sir Keir said: ‘There was a due diligence exercise that culminated in questions being asked because I wanted to know the answer to certain issues.

‘That’s why those questions were asked. The answer to those questions were not truthful.

‘There was then, I should add, security vetting carried out independently by the security services, which is an intensive exercise that gave him clearance for the role, and you have to go through that before you take up the post.

‘Clearly, both the due diligence and the security vetting need to be looked at again.

‘I’ve already strengthened the due process. I think we need to look at the security vetting because it now transpires that what was being said was not true. And had I known then, what I know now, I’d never have appointed him in the first place.’

On September 16 last year, Yvette Cooper – by then Foreign Secretary – and Sir Olly wrote to the Foreign Affairs Select Committee in response to questions about the vetting.

‘Peter Mandelson’s security vetting was conducted to the usual standard set for developed vetting in line with established Cabinet Office policy,’ the letter said.

However, it did not mention that UKSV had initially refused clearance. 

Labour MP Bell Ribeiro-Addy said: ‘The Government must come clean about why the Foreign Office overrode security officials’ decision to deny Mandelson clearance.

‘This scandal has been beyond damaging, as has the Government’s handling of it. We need the full facts.’

The Prospect union, which represents vetting officers at UKSV, accused No10 of allowing the ‘impression to circulate’ that people had not done their jobs properly. 

General Secretary Mike Clancy said: ‘It is deeply unfortunate that following the resignation of Morgan McSweeney Downing Street allowed the impression to circulate that the vetting of Peter Mandelson had not been done correctly by UK Security Vetting.

‘Not only were UKSV put in an invidious position by being asking to conduct vetting after an appointment had been announced, but now deeply troubling reports have appeared in in the media claiming that UKSV advice was overruled.

‘Civil Servants, particularly those working in the most sensitive parts of government cannot speak publicly, and deserve ministers to take responsibility for the decisions they take and not to seek to deflect blame onto them.’

Senior Tory MP David Davis suggested Sir Keir must have known if Mandelson had failed his security vetting.

The ex-Cabinet minister posted on X: ‘In what sort of Government does the Foreign Office override a vetting failure for the most senior ambassadorship in the world without notifying the Prime Minister?

‘It must be presumed that Starmer knew of this vetting failure when he officially appointed him.

‘Frankly, this calls into question the Prime Minister’s claims that he made the decision because Mandelson had lied to him, since he would have had the accurate conclusions of the vetting process when he made the decision.’

It previously emerged that Sir Keir did not speak to Mandelson personally before appointing him as US ambassador.

The PM is said to have left his aides to ask questions about his ties to Epstein.

That was despite being presented with evidence that Mandelson’s friendship with the financier had continued after he was jailed.

National security adviser Jonathan Powell also expressed misgivings during the process.

However, Sir Keir went ahead, after apparently agreeing with chief of staff Morgan McSweeney on three questions that Mandelson needed to be asked.

Mr McSweeney resigned in February saying he took full responsibility for the appointment going ahead. 

Mandelson was arrested on February 23 on suspicion of misconduct in public office, having been accused of passing sensitive information to Epstein during his time as business secretary under Gordon Brown.

He was subsequently bailed, but later handed his passport back and freed under investigation. He has denied any criminal wrongdoing or acting for personal gain.