Maguire now heads the US National Counter-Terrorism Center.
"I am pleased to inform you that the distinguished Joseph Maguire, current director of the National Counter-Terrorism Center, will be appointed acting director of the National Intelligence from August 15," Trump wrote.
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Note that last week, Trump announced that he could appoint Sue Gordon the acting director of the agency, managing 17 civilian and military intelligence services, including the CIA, after its head Dan Coates announced his intention to resign from August 14.
However, on Thursday, the US president said that Gordon also intends to leave on August 15.