The New York Times reported that White House Economic Advisor Gary Cohn plans to resign:

The officials insisted there was no single factor behind the departure of Mr. Cohn, who heads the National Economic Council. But his decision to leave came after he seemed poised to lose an internal struggle amid a Wild West-style process over Mr. Trump’s plan to impose large tariffs on steel and aluminum imports.

“Gary has been my chief economic adviser and did a superb job in driving our agenda, helping to deliver historic tax cuts and reforms and unleashing the American economy once again,” Mr. Trump said in a statement to The New York Times. “He is a rare talent, and I thank him for his dedicated service to the American people.”

Mr. Cohn is expected to leave in the coming weeks. He will join a string of recent departures by senior White House officials, including Mr. Trump’s communications director and a powerful staff secretary.

In a statement, Mr. Cohn said he had been pleased to work on “pro-growth economic policies to benefit the American people, in particular the passage of historic tax reform.” White House officials said that Mr. Cohn was leaving on cordial terms with the president and that they planned to continue discussing policy even after his departure.

I am not seeing a definite date of his last day in his position.