Story highlights Professor steps down as State Dept. science envoy, spelling out "impeach" in his resignation letter

Washington (CNN) A University of California-Berkeley energy professor resigned Wednesday from his position as a State Department science envoy, blasting President Donald Trump for recent comments on white supremacist violence in Charlottesville.

The professor, Daniel Kammen, included a less-than-subtle assessment of Trump in his resignation letter by spelling out the word "impeach" with the first letters of each paragraph.

"My view on impeachment is perhaps less formal than if I was an elected member of Congress," Kammen said in an interview with CNN, "but I don't view what the President is doing as consistent with the best interests of the United States and the global community."

The subliminal message was also meant as an homage to a similar letter penned earlier this month by the Committee on the Arts and The Humanities in which the first letters of each paragraph spelled out the word "resist."

Kammen published his full resignation letter in a tweet Wednesday morning, writing, "Mr. President, I am resigning as Science Envoy. Your response to Charlottesville enables racism, sexism, & harms our country and planet."

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