President Donald Trump has publicly disagreed with the U.S.’s top infectious disease expert Dr. Anthony Fauci, over restarting the NFL. While Fauci is still skeptical about restarting the NFL season due to the COVID-19 pandemic, Trump simply dismissed Fauci’s views via Twitter.

“Tony Fauci has nothing to do with NFL Football. They are planning a very safe and controlled opening,” Trump tweeted. “However, if they don’t stand for our National Anthem and our Great American Flag, I won’t be watching!!!”

On Thursday, Fauci told CNN that NFL teams would require “bubble” protocols already been implemented by the NBA and MLS. However, even with this protocol, Fauci still couldn’t guarantee the complete safety from COVID-19.

“Unless players are essentially in a bubble, insulated from the community and they are tested nearly every day, it would be very hard to see how football is able to be played this fall,” Fauci said. “If there is a second wave, which is certainly a possibility and which would be complicated by the predictable flu season, football may not happen this year.”