"I think it will be a brutal confirmation hearing," Sen. Mark Warner said of Mike Waltz. "I think he's going to have tough questions."

National security adviser Mike Waltz is leaving his White House post, although soon after reports about his departure were published, President Trump announced he plans to nominate him to be ambassador to the United Nations.

The move by Trump comes after hours of speculation that Mike Waltz was about to lose his job as national security adviser.