White House chief of staff John Kelly signed off on a plan that would flush out some of the department’s midlevel and junior aides, according to three people familiar with the situation. White House press secretary Sarah Huckabee Sanders and other key senior officials are expected to remain, these people said.

Though changes to the structure of the White House communications office had been under consideration for months, sparked by concerns about a lack of organization in the office, the recent leak of a junior staffer’s callous remarks about Arizona Republican Sen. John McCain’s health served as a breaking point that moved the president to action.

Trump spoke to the staffer, communications aide Kelly Sadler, during a meeting earlier this month in which he asked Sadler and others present to identify leakers in the communications shop, according to two of the people familiar with the internal discussions. He also expressed deep frustration with the leaks coming out of the White House, telling aides he believes many of the stories that cite leaked information are inaccurate and damage his presidency.