Former No 10 aide McSweeney tells MPs he made a 'serious error' in recommending Mandelson

Morgan McSweeney told MPs on Tuesday that he was wrong to recommend Peter Mandelson for the Washington ambassador job. (committees.parliament.uk) Appearing before the House of Commons Foreign Affairs Committee on April 28, Starmer’s former chief of staff said his advice to the prime minister had been “a serious error of judgment.” (committees.parliament.uk) The committee session was part of Parliament’s inquiry into how Mandelson was vetted for the role of British ambassador to the United States. McSweeney gave evidence at 11:00 a.m. after former Foreign Office permanent under-secretary Philip Barton appeared earlier the same morning. (committees.parliament.uk 1) (committees.parliament.uk 2) The row widened after Keir Starmer told the House of Commons on April 20 that Foreign Office officials had granted Mandelson developed vetting clearance on January 29, 2025, despite a recommendation from United Kingdom Security Vetting that it should be denied. (parliament.uk) Starmer said he learned that on April 14, 2026, and told MPs that he “should not have appointed Peter Mandelson,” adding an apology to Jeffrey Epstein’s victims. (parliament.uk) McSweeney’s evidence was aimed at a narrower question: whether Downing Street leaned on officials to wave Mandelson through. He denied exerting improper pressure and denied responsibility for the national security vetting process itself. (aol.com) (committees.parliament.uk) That matters because earlier witnesses had described sustained pressure around the appointment. The committee had already heard evidence from former senior officials as it traced who knew what, and when, inside the Foreign, Commonwealth and Development Office and No. 10. (committees.parliament.uk 1) (committees.parliament.uk 2) McSweeney’s appearance also put a political relationship under scrutiny. He has long been seen in Westminster as close to Mandelson, and MPs pressed him on how strongly he pushed the case for the appointment. (committees.parliament.uk) (ibtimes.co.uk) The broader fallout has already reached beyond the committee room. McSweeney resigned in February over his role in Mandelson’s appointment, and opposition parties have tried to turn the vetting failure into a wider test of Starmer’s judgment and candor to Parliament. (standard.co.uk) (bbc.com) By Tuesday, McSweeney’s core line was simple: he backed Mandelson, he got that call wrong, and he says the vetting decisions were not his to make. MPs are still using the committee’s inquiry to test whether that account is complete. (committees.parliament.uk)