(CNBC) — White House chief economic advisor Gary Cohn has resigned from President Donald Trump’s administration.

The former Goldman Sachs president and free trade advocate Cohn, whose depature has yet to be announced, departs after Trump announced he would impose stiff tariffs on steel and aluminum imports.

“Gary has been my chief economic advisor and did a superb job in driving our agenda, helping to deliver historic tax cuts and reforms and unleashing the American economy once again,” Trump said.

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