Longtime Trump insider May Davis Mailman has departed the White House, sources told CBS News, making her the highest-ranking official to leave so far during the second term without being pushed out.

Mailman's last day as deputy assistant to the president and senior policy strategist was Friday, one of the sources said. 

But Mailman will become a special government employee to tie up loose ends on some of the policy work she's been involved with, two of the sources said.

She has told colleagues she is starting a government affairs firm, but has said she won't take on clients related to a limited number of administration projects, which include negotiations with Harvard University over frozen federal research funding.

Mailman, who worked all four years of President Trump's first term — with stints in the staff secretary's office, the chief of staff's office and the White House counsel's office — was considered a seasoned hand for helping start up the inner workings of the second White House, two sources said.

She is known for being close to Deputy Chief of Staff Stephen Miller.