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.

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.

Longtime aide has said he takes ‘full responsibility’ for advising PM to appoint Peter Mandelson as US ambassador