White House economic adviser Gary Cohn is resigning, according to the New York Times.

While no specific reason for his departure was given, the former Goldman Sachs COO has voiced strong opposition to President Trump’s proposed steel and aluminum tariffs, a position shared by many, even in the Republican party.

RNC spokesperson Kayleigh McEnany spoke with Cheddar before the news broke and said that, while it’s fine to have differing opinions within the GOP, ultimately Republicans have “to stand behind the president.”

“He is the only Republican that has won a national election,” she said. “He is the voice of our party, unmistakably.

“People forget that he got 13.3 million Republican votes. That’s more than any other nominee in the party’s entire history. Republicans like the Trump messaging. Republicans like the Trump tariffs.”

Critics of the president’s tariffs argue that the import taxes could ignite a trade war with U.S. allies and have a catastrophic effect on the economy. Earlier on Tuesday House Speaker Paul Ryan called for a more “targeted” plan to avoid potential retaliation.