The ongoing inquiry into Peter Mandelson's vetting clearance has revealed new complexities beyond the familiar tensions between ministers and civil servants. Cat Little, the senior civil servant at the Cabinet Office, testified to parliament this week, providing detailed evidence about internal disputes over the handling of Mandelson’s security vetting, shedding light on procedural irregularities and debates within government departments.

Little’s testimony, presented to the foreign affairs select committee, came shortly after that of Olly Robbins, her former counterpart at the Foreign Office, who had offered a more measured account regarding why Mandelson was granted security clearance despite initial advice against it from vetting officials in January 2025. Unlike Robbins, Little brought with her an audit trail of documents, which highlighted Robbins’ refusal earlier this year to share crucial files relating to Mandelson's vetting with her department.

According to Little, Robbins resisted providing a summary that outlined the initial refusal of vetting clearance to Mandelson. This document was subsequently obtained directly from UK Security Vetting (UKSV), a body within the Cabinet Office, after Little made the uncommon decision to bypass Robbins to comply with a parliamentary “humble address” seeking all relevant records. The summary describing the vetting process was reported to be approximately 10 pages long, indicating a level of detail beyond previously known information.

Little also revealed internal discussions within the Foreign Office regarding whether Mandelson required security vetting at all. While there was debate, the consensus advised that vetting was necessary, despite a commonly held assumption due to Mandelson’s status as a peer in the House of Lords that he might be exempt. Little said the final decision on vetting responsibility rested with the Foreign Office.

Notably, Little indicated that there appeared to be no official record of Prime Minister Keir Starmer approving Mandelson’s appointment as ambassador, a departure from normal practice where such decisions are typically documented. Starmer sacked Mandelson in September 2025 following revelations about the former minister’s links to the late convicted sex offender Jeffrey Epstein. Four days after Mandelson's dismissal, the Foreign Office's security team requested access to vetting documents, which UKSV provided.

In response to opposition criticism regarding the flow of information, Starmer stated that claims he was not informed about Robbins’ decisions or that he acted dishonestly were unfounded.

Little defended the timing between when she became aware in late March of Mandelson’s blocked vetting and when she informed the prime minister in April. She said she had to carefully navigate legal and procedural obligations before sharing such sensitive information, emphasizing that her actions were both appropriate and timely.

The inquiry continues next week with further evidence expected from former Downing Street chief of staff Morgan McSweeney and Robbins’ predecessor at the Foreign Office, Sir Philip Barton. The testimony to date underscores ongoing disputes regarding transparency and due process within the highest levels of government during Mandelson’s controversial appointment and subsequent dismissal.