FDA Commissioner Hahn denies reports he was threatened with firing

FDA Commissioner Stephen Hahn on Saturday pushed back on reports that he was threatened with firing.

Sources familiar with the matter told ABC News that in a Friday phone call, White House chief of staff Mark Meadows suggested to Hahn that his job could be on the line if his agency didn’t authorize emergency use of the Pfizer-BioNTech vaccine by the end of the day.

The Pfizer-BioNTech vaccine was authorized by the FDA late Friday.

“Representations in the press that I was threatened to be fired if we didn’t get it done by a certain date is inaccurate,” Hahn told reporters on a Saturday morning call.

Hahn said Saturday that the vaccine was authorized late Friday because science and data determined it was ready, not because of “any other external pressure” and that he would “absolutely” take the vaccine.

Hahn's comments come after President Donald Trump voiced his resistance Friday morning to turning over distribution of coronavirus vaccines to the incoming Biden administration, tweeting "they want to come in and take over one of the ‘greatest and fastest medical miracles in modern day history.'" He slammed the FDA as a "big, old, slow, turtle" moments after Health and Human Services Secretary Alex Azar told ABC's "Good Morning America" that emergency authorization use of Pfizer's coronavirus vaccine was imminent and vaccinations could start as early as Monday. Trump even called out Hahn personally in his tweet, saying "Stop playing games and start saving lives!!!"

The tweet followed months of Trump pressuring the FDA to speed up its process for approving vaccinations.

Trump has for months publicly pressured the FDA to act faster on authorizing COVID-19 treatments -- even when they had not been proven to be effective. During the campaign, Trump openly expressed his desire for a vaccine to become widely available by Election Day, which did not happen.

Shortly after the election, he again bragged about the vaccine effort, which he dubbed "Operation Warp Speed," calling it "unequaled and unrivaled anywhere in the world, and leaders of other countries have called me to congratulate us on what we’ve been able to do."

Despite his repeated efforts to take credit for the record pace at which scientists have developed a vaccine for the novel coronavirus, Trump was uncharacteristically silent after the United Kingdom became the first nation to authorize a COVID-19 vaccine.

That day, Meadows summoned Hahn for a second meeting at the West Wing in as many days, a senior administration official told ABC News.

Reports also emerged this month that the U.S. over the summer declined to purchase additional doses of Pfizer's vaccine. The administration had committed to buying 100 million doses -- enough to cover 50 million people, since the vaccine consists of a two-dose regimen -- but, according to a senior administration official, it had passed on the chance to lock in hundreds of millions more.

The White House denied the reports. But the administration's July announcement about its contract with Pfizer noted that Pfizer left open the option for the U.S. "to acquire an additional 500 million doses."

ABC News’ Katherine Faulders, Anne Flaherty, Ben Gittleson, John Parkinson, Libby Cathey and John Santucci contributed to this report.