President Donald Trump’s chief economic adviser Gary Cohn resigned Tuesday with markets and major ETFs down after hours.

As of 7 pm Eastern, Dow futures were down 326 points after hours, or 1.31% percent, at 24,538.00. The largest ETF, SPDR S&P 500 ETF Trust (SPY), was down 1.15% from the close of trading while the PowerShares QQQ ETF (QQQ) was lower by 1.18%.

“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. He is a rare talent, and I thank him for his dedicated service to the American people,” Trump said in a statement.

Trump’s decision to impose stiff tariffs on steel and aluminum imports struck a strong cord of disagreement with Cohn, former Goldman Sachs president and chief operating officer who strongly opposes tariffs.

After less than 14 months in his role as The White House Economic Council director, Cohn’s exit is icing on the cake after a handful of goodbyes from other top officials in the administration.

In a prepared statement provided by the White House, Cohn said, “I am grateful to the President for giving me this opportunity and wish him and the Administration great success in the future.”

Trump believes he is making America great again by strengthening the U.S. manufacturing segment, recently tweeting, “To protect our Country we must protect American Steel! #AMERICA FIRST,” while Cohn believes these stiff tariffs will cause price increases for steel and aluminum products. The administration is still working on the exact details of the tariffs.

CNN reports that questions about Cohn’s status inside the West Wing returned in the last week after Trump announced his plans to slap tariffs on steel and aluminum imports.

“That suspicion was furthered on Tuesday — hours before the White House announced his plans to resign — when Cohn was absent from a joint news conference the President was holding at the White House,” CNN reports.

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