Senior colleague tried to topple British PM, and top aides resign as Epstein files have ripple effects far beyond US.

British Prime Minister Keir Starmer's chief of staff resigned over the furor surrounding the appointment of Peter Mandelson as the U.K. ambassador to the U.S.

Morgan McSweeney said he took responsibility for advising the British prime minister to appoint Peter Mandelson despite his ties to Jeffrey Epstein.