Dr. Anthony Fauci, the government's top infectious disease expert, was forced to contradict President Trump's tweet touting a cure for the deadly COVID-19 cure, calling Trump's suggesting purely "anecdotal."

"I don't want to embarrass him," Fauci told The New York Times on Saturday. "I don't want to act like a tough guy, like I stood up to the president. I just want to get the facts out. And instead of saying, 'You're wrong,' all you need to do is continually talk about what the data are and what the evidence is."

On Saturday, Trump tweeted to his millions of followers that an anti-malaria drug was the cure for the virus, despite health officials' warnings that not enough is known about its effects to draw a conclusion. 

But some say that the drugs taken together could prove to be fatal.

"Many of the things out there are what I have called 'anecdotal reports,'" Fauci told reporters at a press briefing. "The information that you're referring to specifically is anecdotal. It was not done in a controlled clinical trial, so you really can't make any definitive statement about it."

Trump tweeted that "HYDROXYCHLOROQUINE & AZITHROMYCIN, taken together, have a real chance to be one of the biggest game changers in the history of medicine."

"I'm not totally sure what the president was referring to," Fauci said. "Many things you hear out there are what I call anecdotal reports. They may be true, but they're anecdotal. .. If you really want to definitively know if something works, you have to do the kind of trial that you get the good information with."