LONDON, April 17, 2026 (BSS/AFP) - UK Prime Minister Keir Starmer faced mounting pressure to quit on Friday over his appointment of Peter Mandelson as envoy to Washington, after it emerged the veteran politician had failed security vetting. The affair has haunted Starmer for months amid growing anger over Mandelson's 2024 nomination to the top diplomatic post despite his close ties to late US sex offender Jeffrey Epstein. Mandelson, a longtime insider with Starmer's ruling Labour party, has held multiple ministerial posts since the late 1990s -- but has been dogged by repeated scandals throughout his career. The government has blamed foreign ministry officials for the latest debacle, saying neither Starmer nor his foreign minister were told about Mandelson's failed security check until this week. The top civil servant in the foreign ministry, Olly Robbins, has now quit after Starmer "lost confidence in him" over the failure to tell him "about this decision", senior minister Darren Jones said on Friday. Foreign ministry officials made the decision to allow Mandelson's appointment to proceed "against the recommendation of UK Security Vetting", the government said on Thursday. Calls by opposition politicians for the prime minister to resign intensified Thursday as the government confirmed an initial report by the Guardian newspaper that had been appointed even after failing the background security check. The ambassador to Washington is seen as Britain's most prestigious and most important diplomatic post, in charge of nurturing the so-called "special relationship" with President Donald Trump. - 'Furious' - Earlier in the year, two of Starmer's top political aides resigned over the scandal amid the growing political storm. Starmer has faced repeated questions about his judgment in selecting Mandelson, who he sacked in September last year only months after the former minister took up the post. Opposition right-wing Conservative Party leader Kemi Badenoch wrote on X that "Starmer has betrayed our national security. He should go". The prime minister has accused Mandelson of lying about the extent of his ties to Epstein during the vetting process. Jones said Friday it was "unacceptable" that the foreign ministry had overruled the vetting process, and denied the premier had misled parliament, calling the error-strewn process "a failure of the state". "You can imagine he (the PM) was furious as you would expect that he was only told about this on Tuesday evening," Jones told Sky News, adding Starmer would address parliament on Monday. He also denied that Starmer's position was at risk. The "public can see in Keir Starmer that they have a strong, credible leader who has influence on the world stage," he insisted. - Police investigation - Starmer fired Mandelson as ambassador after documents released by a US Congressional committee revealed new details about the depth of his ties to Epstein. Police have now opened an investigation into allegations of misconduct in office by Mandelson, who was arrested and released on bail in February. He has not been charged and denies criminal wrongdoing. The force is investigating Mandelson over allegations he leaked sensitive documents to Epstein when he was a government minister, including during the 2008 financial crash. The due diligence advice submitted to Starmer in December 2024 noted a series of reports detailing Mandelson's links with Epstein, who was convicted of sex crimes in Florida in 2008, including soliciting a minor. It said their relationship "continued across 2009-2011", beginning when Mandelson was a government minister and continuing after the end of the UK's last Labour government in 2010. It also noted that Mandelson "reportedly stayed in Epstein's house while he was in jail in June 2009". Lawmakers earlier this year ordered the Labour government to release tens of thousands of emails, messages and documents detailing how Mandelson was vetted for the role. The second tranche of documents is expected to be released in the coming weeks.