Barton and McSweeney face MPs over Mandelson vetting row

Sir Philip Barton told MPs that Lord Mandelson’s path to Washington was handled on a “compressed timescale”, with a diligence document already drawn up before Barton was even told about the appointment on 15 December 2024. His evidence, given to the Foreign Affairs Committee in the Grimond Room at Portcullis House, went to the heart of how senior foreign-policy posts are checked, recorded and challenged inside government.

Barton, who was the Foreign, Commonwealth and Development Office’s permanent under-secretary from September 2020 to January 2025, said Downing Street presented him with a decision and told him to “get on with it”. He also said the prime minister had been informed of the risks and had accepted them. Live reporting from the hearing said Barton described it as “odd and insufficient” that Mandelson had not been vetted earlier, sharpening the committee’s focus on whether the system properly tests high-risk appointments or simply documents decisions that have already been made.

The session came as MPs continued scrutiny of the security vetting process behind Mandelson’s appointment as British ambassador to Washington. Barton’s appearance was scheduled for 9.00am on 28 April 2026, followed by Morgan McSweeney at 11.00am. McSweeney, the former No 10 chief of staff who resigned in February 2026 over his role in advising Starmer to appoint Mandelson, was expected to face questions about how far he was involved in the process and whether political urgency overrode normal checks.

The stakes extend far beyond one envoy. Sir Keir Starmer sacked Mandelson in September 2025 over his links to convicted sex offender Jeffrey Epstein, and the prime minister now faces a Commons vote over whether he should be referred to Parliament’s Privileges Committee over claims he misled MPs about the appointment. Conservative leader Kemi Badenoch has accused Starmer of misleading Parliament, turning the vetting row into a test of ministerial accountability as well as personal judgment.

The hearing also highlighted gaps in the paper trail around scrutiny itself. The committee had sought evidence from Ian Collard, a Foreign Office security official, but reports said he would not appear before MPs. Barton has also suggested that the dismissal of Sir Olly Robbins, after the failure to tell No 10 of the security services’ recommendation against Mandelson’s appointment, may not have followed the usual disciplinary process used in serious FCDO cases. Together, those details point to a system in which risk was known, but the challenge mechanisms around it may have been too weak, too slow or too easily overridden.