Another high-profile member of the Trump administration has walked away from the White House.

Tuesday afternoon, it was announced that Donald Trump's top economic adviser Gary Cohn is resigning. At one point, the former Goldman Sachs Group executive was rumored as a potential pick to replace John Kelly as the next chief of staff. But Cohn's relationship with Trump soured after he disapproved of the way the president handled last year's Charlottesville white supremacist rally. He even even went as far as to draft a resignation letter before opting to patch things up with his boss.

So what finally moved Cohn to retire? Sources close to him are saying that the final straw came amid strong disagreements with Trump's decision to impose tariffs on steel and aluminum imports.

In a statement released Tuesday, Trump said, "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."

In a statement of his own, Cohn said, "It has been an honor to serve my country and enact pro-growth economic policies to benefit the American people, in particular the passage of historic tax reform. I am grateful to the President for giving me this opportunity and wish him and the Administration great success in the future."

It didn't take long for Trump to tweet about Cohn's departure and the ensuing search for his replacement.

Cohn's departure comes in the wake of the resignation of another Goldman Sachs alum, deputy national security adviser Dina Powell. And with White House communications director Hope Hicks having resigned last week, Trump's administration is as volatile as ever.