Director of the National Economic Council Gary Cohn was the leading internal opponent to Trump's planned tariffs on imports of steel and aluminum, to try to get Trump to reverse course.
Top economic adviser Gary Cohn is leaving the White House after breaking with President Donald Trump on trade policy, the latest in a string of high-level departures from the West Wing.
Cohn, the director of the National Economic Council, has been the leading internal opponent to Trump's planned tariffs on imports of steel and aluminum, working to orchestrate an eleventh-hour effort in recent days to get Trump to reverse course.
But Trump resisted those efforts, and reiterated on Tuesday he would be imposing tariffs in the coming days.
Cohn's departure comes amid a period of unparalleled tumult in the Trump administration, and aides worry that more staffers may soon head for the doors.
The announcement came hours after Trump denied there was chaos in the White House.
Trump maintained that his White House had "tremendous energy," but multiple White House officials said Trump had been urging anxious aides to stay.
"Everyone wants to work in the White House," Trump said during a joint press conference with Swedish Prime Minister Stefan Löfven. "They all want a piece of the Oval Office."
In a statement, Cohn said it was his honour to serve in the administration and "enact pro-growth economic policies to benefit the American people."
Trump praised Cohn despite the disagreement on trade, issuing a statement saying Cohn had "served his country with great distinction."
Cohn is a former Goldman Sachs executive who joined the White House after departing the Wall Street firm with a $285 million payout. He played a pivotal role in helping Trump enact a sweeping tax overhaul, co-ordinating with members of Congress.
Trump loved to boast about the former executive's wealth, but Cohn's tenure in the White House was rocky.
Cohn nearly departed the administration last summer after he was upset by the president's comments about the racial violence in Charlottesville, Virginia. Cohn, who is Jewish, wrote a letter of resignation but never submitted it.
"Citizens standing up for equality and freedom can never be equated with white supremacists, neo-Nazis, and the KKK," Cohn told The Financial Times at the time.
"I believe this administration can and must do better in consistently and unequivocally condemning these groups and do everything we can to heal the deep divisions that exist in our communities."
The comments came as Cohn was under consideration to serve as chairman of the Federal Reserve.
Earlier in the administration, Cohn found himself on the losing side of several contentious battles, including the announcement of plans to pull the United States from the Paris Climate Agreement.
Cohn had also hoped to steer more than $1 trillion into infrastructure investments, including updates to the US air traffic control system that would make air travel faster and easier.
But the multiple infrastructure rollouts by the Trump administration failed to gain traction, often overshadowed by controversial statements made by the president himself.
Cohn often faced ridicule among some inside the White House for being a registered Democrat who last year met with former Republican officials pushing a form of a carbon tax that was designed to reduce the risks from climate change.
Yet his stock improved to the point that he was one of names Trump was floating for chief of staff last month, when it looked like John Kelly was on thin ice.
Cohn told other White House aides in recent weeks that he would have little reason to stay if Trump followed through with his tariff plans, according to a White House official familiar with his views. The official spoke on condition of anonymity.
"I mean it is no secret that he disagreed with Trump on trade and he was opposed to the policy," said Stephen Moore, who served as an economic adviser to Trump's campaign.
The White House did not immediately announce a replacement for Cohn, whose deputy, Jeremy Katz, departed in January. Among those under consideration for Cohn's job are CNBC commentator Larry Kudlow and Office of Management and Budget director Mick Mulvaney, according to a person familiar with the discussions.
In a tweet earlier Tuesday, Trump sought to portray himself as the architect of the White House staff changes, writing, "I still have some people that I want to change (always seeking perfection)."
The new Fake News narrative is that there is CHAOS in the White House. Wrong! People will always come & go, and I want strong dialogue before making a final decision. I still have some people that I want to change (always seeking perfection). There is no Chaos, only great Energy!— Donald J. Trump (@realDonaldTrump) March 6, 2018
Trump acknowledged he was a tough boss to work for, saying he enjoyed watching his closest aides fight over policy. "I like conflict," he said during the press conference.
Cohn was nowhere in sight at the press conference and a seat reserved for him in the East Room was filled by a different aide.
Dating back to the campaign, Trump has frequently and loudly complained about the quality of his staff, eager to fault his aides for any mishaps rather than acknowledge any personal responsibility.
But the attacks on his own staff have sharpened in recent weeks, and he has suggested to confidants that he has few people at his side he can count on, according to two people familiar with his thinking but not authorised to publicly discuss private conversations.
Coinciding with the heated debate over tariffs, Trump's communications director Hope Hicks, one of his closest and most devoted aides, announced her resignation last week, leaving a glaring vacancy in the informal cadre of Trump loyalists in the White House.
Turnover after just over a year in office is nothing new, but the Trump administration has churned through staff at a dizzying pace since taking office last January, and allies are worried the situation could descend into a free fall.
Making matters worse, the list of prospects to replace departing aides grows shorter as the sense of turmoil increases. Vacancies abound throughout the West Wing and the administration at large, from critical roles like staff secretary to more junior positions in the press office.