Watch: Trump speaks at military base in California


[The stream is slated to start at 5 p.m. ET. Please refresh the page if you do not see a player above at that time.]

President Donald Trump is set to give remarks to members of the military on Tuesday.

Trump's speech, to be delivered at a Marine Corps air station in California, will be made against a backdrop of high-level White House departures, including his top diplomat and top economic advisor.

Reports on Tuesday morning that Secretary of State Rex Tillerson had been fired were validated by a tweet from Trump shortly after.

Trump tweet: Mike Pompeo, Director of the CIA, will become our new Secretary of State. He will do a fantastic job! Thank you to Rex Tillerson for his service! Gina Haspel will become the new Director of the CIA, and the first woman so chosen. Congratulations to all!

Tillerson, in a press conference at the State Department, said he would relinquish his duties to a temporary successor by the end of the day.

A statement from Tillerson's department said he "did not speak to the President and is unaware of the reason" for his removal. The Trump administration, claiming that the statement misrepresented the White House's version of events, fired the staffer who wrote it, NBC News reported.

Trump's personal assistant, former college quarterback John McEntee, was also fired this week. NBC News reported McEntee was under a Secret Service investigation relating to financial crimes.