British Prime Minister Keir Starmer said on Monday he had been wrong to appoint Labour politician Peter Mandelson as UK envoy to Washington, seeking to quell anger over a scandal surrounding convicted sex offender Jeffrey Epstein’s long-time associate.Starmer, whose popularity with the British public and many MPs in his own centre-left Labour Party has slumped, has also struggled to manage a controversy that threatens to bring down his leadership.Addressing parliament about the deepening political row, Starmer said: “At the heart of this, there is also a judgment I made that was wrong. I should not have appointed Peter Mandelson.”He faced fresh calls to quit last week after it was revealed that Mandelson, whose friendship with the late disgraced New York financier was long known, had become Britain’s envoy to Washington last year despite failing security checks.Starmer has insisted that he and other ministers were not told until last week that Mandelson had failed the independent vetting process.”It beggars belief that throughout the whole timeline of events, officials in the Foreign Office saw fit to withhold this information from the most senior ministers in our system, in government,” he told MPs.”If I had known before he took up his post that (the) recommendation was that developed vetting clearance should be denied, I would not have gone ahead with the appointment.”Due processLast Thursday, Starmer sacked the UK Foreign Office’s top civil servant, Olly Robins, telling MPs that he had set in motion a review of the security vetting process.But ex-civil servants have accused Starmer of scapegoating Robbins, who will give his own account to a parliamentary watchdog committee on Tuesday.Opposition leaders have called for the Labour leader to step down, with accusations ranging from incompetence to wilful misleading of parliamentarians and the public.Starmer told parliament in February that “full due process” was followed when Mandelson was vetted and cleared for the key role.His Downing Street office has insisted that remains true because government rules meant the UK Foreign Office had the power to overrule vetting concerns, without the knowledge of Starmer and his top team.On Friday, Downing Street took the unusual step of releasing a memo that insisted he had only found out about the vetting failure last Tuesday. Senior ministers have so far rallied around Starmer.”A judgement was made that the Trump administration was an unconventional administration and an unconventional ambassador could do a job for the United Kingdom,” Scotland Secretary Douglas Alexander said Monday.”That judgement was wrong and the prime minister accepts that.”Calls to step downOther ministers have argued that Starmer should remain in power amid global turmoil sparked by the Iran war in and other issues, including forging closer relations with the EU.But polls suggest Starmer is one of Britain’s most unpopular prime ministers ever.Starmer sacked Mandelson in September 2025, seven months after he took up the post, after new details emerged about the depth of the ex-envoy’s ties to Epstein, who died in a US prison in 2019 while facing sex-trafficking charges.UK police are investigating allegations of misconduct in office by Mandelson, 72, when he was a Labour minister more than 15 years ago. He was arrested and released in February.Mandelson has not been charged and denies criminal wrongdoing.Starmer and his Labour party are also bracing for a chastening set of local elections next month, including in the devolved Scottish and Welsh parliaments.