Kenneth Frazier, Chairman and CEO of the pharmaceutical company Merck & Co. (Photo by Spencer Platt/Getty Images)

NEW YORK (AP) — The CEO of the nation’s third largest pharmaceutical company is resigning from the President’s American Manufacturing Council citing “a responsibility to take a stand against intolerance and extremism.”

President Donald Trump lashed out almost immediately Monday at Merck CEO Kenneth Frazier on Twitter, saying Frazier “will have more time to LOWER RIPOFF DRUG PRICES!”

Frazier’s resignation comes shortly after a violent confrontation between white supremacists and protesters in Charlottesville, Virginia, that left one person dead and 19 injured.

Frazier said in a tweet on Monday that the country’s leaders must “honor our fundamental values by clearly rejecting expressions of hatred, bigotry and group supremacy.”

Trump is being criticized for not explicitly condemning the white nationalists who marched in Charlottesville.

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