Mandelson inquiry: UK ambassador-designate to Japan faces potential parliamentary summons

The Foreign Affairs Select Committee is preparing to decide whether to summon Corin Robertson, the UK’s ambassador-designate to Japan, to give evidence regarding the controversial decision to grant Peter Mandelson security clearance. Robertson, who served as the Foreign, Commonwealth and Development Office’s chief operating officer during the January 2025 clearance process, is the only senior civil servant involved in the matter who has not yet been questioned by parliament.

A source within the committee indicated that MPs would consider this week whether to call Robertson to provide testimony, either verbally or in writing. Her appearance could be pivotal in resolving unanswered questions about the decision-making process, which has been characterised by a lack of written records and a heavy reliance on oral briefings. The committee is nearing the conclusion of its investigation but is expected to await the release of further documents under the “humble address” system before reaching final conclusions.

The inquiry centres on the decision by Olly Robbins, the FCDO’s most senior civil servant, to grant clearance despite recommendations from United Kingdom Security Vetting (UKSV) to deny it. UKSV advised the department on 29 January 2025 that there was “high” concern regarding Mandelson and that clearance should be refused. Robbins was dismissed by Prime Minister Keir Starmer three weeks ago after it was revealed he had authorised the clearance without informing ministers, a failure Starmer described as “unforgivable”.

Evidence submitted by Ian Collard, the FCDO’s former head of security, has highlighted Robertson’s specific role in the chain of command. Collard stated that he initially discussed Mandelson’s vetting with Robertson before briefing Robbins. According to his evidence, Robertson agreed that risks could be mitigated and advised Collard to take the case to Robbins for a final decision. Collard subsequently sent an email to Robertson and an aide to Robbins noting the decision and mitigations, but the correspondence did not set out the risks identified by UKSV.

The integrity of the inquiry has been further complicated by the absence of audit trails. Both Robbins and Collard testified that they had not read Mandelson’s vetting summary document, relying instead on verbal briefings. The intelligence and security committee has criticised the government for withholding Mandelson’s vetting file and applying redactions “far too broadly”, raising concerns that the files released under the humble address may be incomplete or heavily censored.