Trump Names Hostage Negotiator Robert O'Brien As National Security Adviser

President Donald Trump says he plans to name hostage negotiator Robert O'Brien to be his new national security adviser.

Trump tweeted Wednesday that he has "worked long & hard" with O'Brien and that "he will do a great job!"

Trump's announcement about O'Brien comes a week after he ousted John Bolton from the national security adviser's post, citing policy disagreements.

Bolton was Trump's third national security adviser.