Reports say President Donald Trump will nominate National Security adviser Mike Waltz to become the nation's ambassador to the United Nations.

White House shakeup: Mike Waltz leaves national security role, nominated as UN ambassador Louis Serbeck, 54, died while being rushed to a nearby hospital. A passenger's mobile device was lodged in a seat and caused "an electrical smell," prompting an emergency landing to remove it.

National security adviser Mike Waltz and his deputy, Alex Wong, will be leaving their posts in the Trump White House, according to multiple sources familiar with their departure.