Daniel Kammen, an energy professor at the University of California, Berkeley, resigned Wednesday from his position as the US State Department's science envoy, USA Today reported.
Kammen, who was appointed to the position back in February 2016 and has served in many federal roles for more than 20 years, said his decision was tied to President Donald Trump's "attacks on core values of the United States."
"Your failure to condemn white supremacists and neo-Nazis has domestic and international ramifications," he said. "Particularly troubling to me is how your response to Charlottesville is consistent with a broader pattern of behavior that enables sexism and racism, and disregards the welfare of all Americans, the global community and the planet."
Kammen's letter also had a not-so-subtle message: the first letter of each paragraph spelled out the word "IMPEACH."