But the U.S. last week granted Mandelson his agrément — a diplomatic term for the formal agreement to accept his appointment — according to two people with knowledge of the process, granted anonymity to discuss a sensitive matter.
Mandelson will still need to hand a so-called “letter of credence” to Trump on arrival in Washington, to formalize his acceptance. But that is seen as a rubber-stamping process and it would be highly unusual for the U.S. to grant agrément then U-turn at a later stage.
Mandelson is a veteran political operator who helped overhaul Britain’s center-left Labour Party in the 1990s as it returned from a lengthy spell out of government.
He twice quit amid scandals during the period — but made a striking frontline comeback during Gordon Brown’s administration. He has served as an informal advisor to Labour since Starmer took over its leadership in 2020. Starmer became U.K. prime minister last summer.
A fierce critic of Brexit, Mandelson served as European commissioner for trade for a four-year stint in the 2000s, and has a seat in the House of Lords, the upper chamber of the British parliament.
Mandelson will inherit a packed in-tray from Karen Pierce, who has been in post since 2018.
Crucial issues likely to dominate his first few months include trying to shore up U.S. support for Ukraine and persuading the Trump administration not to hammer the U.K. economy with tariffs on imports.
Daniel Lippman reported from Washington D.C.
