“We're looking at that and that has to be approved by the White House,” Trump said, adding that it “sounds like a political move.” The president is said to believe that a pre-election authorization would translate into a victory for him. He has repeatedly promised that a vaccine would be ready by election day, which is Nov. 3.

While The FDA declined to comment on Trump's remarks, an FDA spokesperson told news broadcaster CNN that the agency’s guidelines must go through White House Office of Management and Budget review process.

Rumors of a move by the health agency to reassure the American public and the worried National Institutes of Health (NIH) that the first vaccines to be approved by the FDA will be safe surfaced earlier this week and speculation focused on tougher guidelines being  announced later in the week.

Without giving any details, FDA commissioner Stephen Hahn told the US Senate Health Committee on Sept. 23 that the "FDA will not authorize or approve a vaccine that we would not feel comfortable giving to our families.” It would have to meet the agency's “rigorous expectations” for safety and effectiveness, he said.

Hahn has come under fire from some in the health sector for repeatedly obliging the president’s requests for EUAs that many were skeptical about.

Peter Hotez, a vaccinologist at Baylor College of Medicine in Texas, told the broadcaster

he was concerned that “there could be a gray zone where a vaccine looks partially protective and it goes on the market without a full formal review process.”