WASHINGTON - President-elect Joe Biden has chosen longtime Washington operative Ronald Klain as White House chief of staff, sending an early signal that he intends to rely heavily on experience, competence and political agility after a Donald Trump presidency that prized flashiness and personality.

Donald Trump announced Friday that his budget director Mick Mulvaney will step in as acting chief of staff to replace John Kelly -- amid indications the president is struggling to fill the key post.