Committee publication · Correspondence · 21 April 2026
Letter from Sir Oliver Robbins KCMG CB, relating to the appointment of Lord Mandelson as Ambassador to the United States, dated 21 April 2026
From: Foreign Affairs Committee
Inquiry: Work of the Foreign, Commonwealth and Development Office
Summary
Sir Oliver Robbins, former Permanent Under-Secretary at the FCDO, responds to the Foreign Affairs Committee's invitation to give evidence on Lord Mandelson's vetting for the US ambassadorship. Robbins sets out clarifications on the security clearance process, emphasizing that Developed Vetting was completed to normal standards despite political pressure, that FCDO (not UKSV) made the final clearance decision, and that the vetting system's confidentiality must be protected.
Key findings
- The Cabinet Secretary recommended security clearance be obtained before announcing Mandelson's appointment in November 2024, but this was not done; only after announcement did discussions about whether Developed Vetting was necessary begin.
- When Robbins took over as PUS on 20 January 2025, due diligence had been completed, royal approval given, the appointment announced, agrément received from the US, and Mandelson already had building and IT access—creating a dismissive approach to DV from Number 10.
- UKSV considered Mandelson a 'borderline' case leaning towards denying clearance; ESND assessed the identified risks could be managed, and Robbins agreed FCDO should grant clearance with appropriate risk management.
- FCDO, not UKSV, is the DV decision-maker; UKSV did not 'fail' Mandelson and FCDO did not 'overrule' them—FCDO makes the final risk judgment on clearance.
- The vetting story leaked to The Guardian within days of Cabinet Office officials briefing Number 10, which Robbins describes as 'deeply worrying'.
Tone
ProceduralTopics
Key actors
Sir Oliver Robbins, Lord Mandelson, Dame Emily Thornberry, Prime Minister, Cabinet Secretary, Foreign Secretary, Minister Doughty, FCDO, UKSV
Notable line
“When the Prime Minister informed the House that the proper process had been followed in respect of NSV, he was correct.”
Key Quotes
“… i. I received a leƩer yesterday dismissing me from my employment: I have sought advice on that leƩer and am not able to discuss this. ii.”
“… this. ii. I ask the CommiƩee to respect my convicƟon that the integrity and confidenƟality of the NaƟonal Security Veƫng (NSV) system must be maintained if it is to be effecƟve.”
“In November 2024, the then Cabinet Secretary recommended that security clearance be obtained before announcing a poliƟcal appointee for Washington. It was not.”
“DV is a clearance process designed to assess a candidate's naƟonal security risk. It relies on the applicant and contacted third parƟes being enƟrely candid. To be effecƟve, this requires a highly confidenƟal environment, which applicants trust to protect their personal informaƟon.”
“UKSV did not 'fail' Mandelson and FCDO did not 'overrule' their decision. Like several other departments eg MOD, FCDO is the DV decision-maker, not UKSV.”
“UKSV considered Mandelson a 'borderline' case, leaning towards recommending that clearance be denied; b.”
“… it is deeply worrying that within days of CO officials briefing No 10 on the issues they perceived with Mandelson's veƫng the story had leaked to The Guardian.”
“My guiding principle has been to defend the integrity of a system designed to protect UK naƟonal security.”
Source · parliament.uk record ↗