Scottish Secretary Dr John Reid will succeed Mr Peter Mandelson as Northern Ireland Secretary.
Dr Reid, 53, among the favourites for the post, spent about 30 minutes at Downing Street tonight.
Dr Reid was a name mentioned in Belfast before the Prime Minister, Mr Tony Blair, gave Mr Mandelson the chance to resurrect his career. He was among three front-runners tipped to take the post in the wake of Mr Mandelson's departure today.
Welsh Secretary Mr Paul Murphy, a former junior minister in Belfast, and Mr Adam Ingram were also considered to be candidates.