Exclusive: A trio of candidates have been interviewed by the PM, but he could still decide to directly appoint someone else

Keir Starmer is poised to choose a new ambassador to Washington from a shortlist of three as relations with the US are tested over Ukraine and Donald Trump’s attacks on European leaders.

The prime minister held interviews with three finalists for the role this week, the Guardian has learned, with Downing Street preparing to make an appointment before the end of the year.