Merck & Co Inc. CEO Kenneth Frazier resigned from President Donald Trump’s American Manufacturing Council following Trump’s response to events that transpired during a white nationalist group’s march in Charlottesville, Virginia, reports Reuters.

At a “Unite the Right” rally on Saturday, a Nazi sympathizer allegedly drove into counterprotesters, killing one person and injuring 19 others. When Trump commented on the situation, he said “many sides” were to blame. He has since been criticized by both Democrats and Republicans for not explicitly denouncing racism and white supremacists.

This didn’t sit well with Frazier, an African American who has been at pharma giant Merck for about 25 years. “America’s leaders must honor our fundamental values by clearly rejecting expressions of hatred, bigotry and group supremacy, which run counter to the American ideal that all people are created equal,” Frazier wrote in his resignation, which he posted on social media. “As CEO of Merck and as a matter of personal conscience, I feel a responsibility to take a stand against intolerance and extremism.”

Not too long after Merck released Frazier’s statement, Trump replied with a tweet of his own, saying, “Now that Ken Frazier of Merck Pharma has resigned from President’s Manufacturing Council, he will have more time to LOWER RIPOFF DRUG PRICES!”

Frazier joins several other executives from U.S. companies that have stepped down from a number of Trump’s presidential advisory councils, including Elon Musk (Tesla Inc.), Bob Iger (Walt Disney Co.) and Travis Kalanick (Uber Technologies Inc).

Merck has manufactured treatments for HIV and hepatitis C, including the integrase inhibitor Isentress, the multiclass combination drug Zepatier and the interferon injectable Pegintron.

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