New Delhi, Feb. 10 -- British Prime Minister Keir Starmer 's chief of staff resigned Sunday over the furor surrounding the appointment of Peter Mandelson as the U.K. ambassador to the U.S. despite his ties to Jeffrey Epstein.

Morgan McSweeney said he took responsibility for advising Starmer to appoint Mandelson, 72, to Britain's most important diplomatic post in 2024.

"The decision to appoint Peter Mandelson was wrong. He has damaged our party, our country and trust in politics itself," McSweeney said in a statement. "When asked, I advised the Prime Minister to make that appointment and I take full responsibility for that advice."

Starmer is facing a political storm and questions about his judgement after newly published documents, par...