Experts will know by early December whether a potential coronavirus vaccine is safe and effective, but widespread availability will probably not happen until next year, Dr. Anthony Fauci said Sunday.

"We will know whether a vaccine is safe and effective by the end of November, beginning of December," the director of the U.S. National Institute of Allergy and Infectious Diseases said. "The amount of doses that will be available in December will not certainly be enough to vaccinate everybody -- you'll have to wait several months into 2021."

Speaking to the BBC's Andrew Marr Show, Fauci added that the vaccination of a "substantial proportion of the population" so there could be a "significant impact on the dynamics of the outbreak" may not be possible until the second or third quarter of 2021.

"What I do foresee is that with a successful vaccine and the continuation of some form of public health measures, as we go and progress through the months of 2021, getting towards the third and fourth quarter, we will see a considerable approach towards some form of normality," Fauci told Marr.

Pressed on whether he believes U.S. President Donald Trump is correct in saying that the United States is "rounding the corner" in the course of the pandemic, Fauci said he believes this is untrue.

"The data speak for themselves," Fauci said.

"Unfortunately, I am sorry to see what I'm viewing from a distance, what I'm seeing in the U.K. ... after getting hit pretty badly the way we did, you went down to a pretty low level, but now you're starting to escalate in the same manner that we are here," he added.