LONDON, April 16 – The prime minister did not know Lord Mandelson failed security vetting for the role of US ambassador until earlier this week, the government has said.
A spokesperson said the decision to go against the recommendation of the vetting agency and allow him to take up the role was taken by officials in the Foreign Office.
Sir Keir Starmer has faced calls to resign over allegations he misled Parliament and MPs when he claimed “full due process” was followed during the appointment.
It came after the Guardian newspaper reported that Lord Mandelson was initially denied security clearance in late January 2025 but this was overruled by the Foreign Office to ensure the peer could take up the post.
Lord Mandelson was sacked as Ambassador last year over his ties to the late convicted sex offender Jeffrey Epstein.
During Prime Minister’s Questions on 10 September 2025, Sir Keir said three times that “full due process” was followed for the appointment.
The Ministerial Code states that ministers who knowingly mislead Parliament are expected to resign.
Taking questions from journalists following a press conference on 5 February in Hastings, Sir Keir also said that there was “security vetting carried out independently by the security services, which is an intensive exercise that gave [Lord Mandelson] clearance for the role, and you have to go through that before you take up the post”.
Lord Mandelson was announced as the UK’s Ambassador to the US in December 2024, before in depth vetting had been carried out, and formally took up the role on 10 February 2025.
Conservative leader Kemi Badenoch called for the PM to resign.
“The Prime Minister appointed Peter Mandelson before the vetting had been completed, vetting Mandelson failed,” she said.
“Starmer then said full due process was followed. That is misleading Parliament.
“I’m only holding him to the same standards to which he’s held previous prime ministers – that if they mislead parliament, they should resign.
“In these dangerous times, Britain cannot afford to have a prime minister who the country doesn’t trust. Starmer has betrayed our national security. He should go.”
The revelations have reignited anger over Lord Mandelson’s appointment and raise further questions over the prime minister’s judgement.
Liberal Democrat leader Sir Ed Davey said that if it was true the PM was not aware Lord Mandelson had failed security vetting, he should have “told Parliament at the earliest opportunity, not waited for the media to force the truth out”.
“His failure to do that alone is surely a breach of the ministerial code,” he added.
Reform UK, the Green Party and Plaid Cymru have also called for the prime minister to go, accusing him of lying about Lord Mandelson’s vetting.
Meanwhile, the Scottish National Party have written to the independent adviser on ministerial standards, Sir Laurie Magnus, calling for an investigation into whether the PM deliberately misled the public.
SNP Westminster leader Stephen Flynn said: “The prime minister is either incompetent, gullible or a liar. Or all three.”