(Bloomberg) -- Anthony Fauci, the U.S. government’s foremost expert on infectious disease, said he feels “somewhat” liberated working for President Joe Biden after Donald Trump tried to sideline him.

Fauci, the director of the National Institute of Allergy and Infectious Diseases, addressed reporters from the White House briefing room on Thursday as Biden’s chief medical adviser. Under Trump, Fauci had been displaced by Scott Atlas, a politically conservative neuroradiologist who disparaged face masks, social distancing and other public health precautions.

“The idea that you can get up here and talk about what you know, what the evidence, what the science is and know that it’s, let the science speak, is somewhat of a liberating feeling,” Fauci said.

Fauci acknowledged that he had to contradict Trump at times, such as when the former president advocated for the use of an unproven malaria drug, hydroxychloroquine, to treat Covid-19.

“That really was uncomfortable because they were not based on scientific fact,” Fauci said. “I can tell you I take no pleasure at all in being in a situation of contradicting the president.”

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