The decision to appoint Lord Mandelson to the key diplomatic role has dogged Sir Keir for months and the PM’s statement does not appear to have drawn a line under the issue.
Lord Mandelson was announced as the UK’s ambassador to the US in December 2024, before in-depth vetting had been carried out.
He formally took up the role on 10 February 2025 but was sacked just seven months later over his ties to the late convicted sex offender Jeffrey Epstein.
UK Security Vetting, a specialist agency within the Cabinet Office, began the vetting process in late December 2024, and on 28 January 2025, recommended Developed Vetting clearance should be denied.
But Foreign Office officials went against this advice and granted him clearance.
In his statement, the PM said there had been repeated occasions when they should have told him this.
These included when Lord Mandelson was appointed and when he was sacked, as well as the point at which the PM subsequently ordered a review of the vetting process.
Sir Keir said the then-head of the Civil Service, Sir Chris Wormald, should also have been told when he was asked to review the appointment process last September, describing it as “astonishing” that he had not been.
He added that the information should have been shared with Foreign Secretary Yvette Cooper when she was responding to questions about the appointment from the Commons Foreign Affairs committee last September.
He said it was “absolutely unforgivable” Cooper had not been informed.
“A deliberate decision was taken to withhold that material from me,” he told MPs.
“This was not a lack of asking. This wasn’t an oversight. It was a decision taken not to share that information on repeated occasions.”
The PM said it was “frankly staggering” he had not been told even when he launched a review of the vetting process.
While he accepted “sensitive, personal information” provided during the vetting process should be protected, he rejected the idea ministers could not be told the overall recommendation.
