White House national security adviser Mike Waltz is set to depart the administration, according to two people familiar with the matter on Thursday, marking the first major staff shakeup of President Donald Trump’s second term.

Waltz was on television as late as Thursday morning, promoting the administration’s agreement with Kyiv that would allow the U.S. to access Ukraine’s critical minerals and other natural resources.

President Donald Trump has been in office for 100 days, and reactions to his policies have been partisan and divided. The White House press release proclaimed boldly, President Trump “accomplished more in 100 days than most presidents do over an entire term — and he’s still just getting started.