Dr. Rochelle Walensky, director of the U.S. Centers for Disease Control and Prevention, issued a clarification statement Friday night after claiming on Fox News’ "Special Report" that the U.S. was "looking into" a possible nationwide vaccine mandate.

It was the latest reversal for the health agency, which has drawn criticism for murky communications regarding the coronavirus and policies and recommendations related to the outbreak.

"To clarify," Walensky wrote on Twitter, "There will be no nationwide mandate. I was referring to mandates by private institutions and portions of the federal government. There will be no federal mandate."

Earlier Friday, "Special Report" host Bret Baier had asked Walensky, "Are you for mandating a vaccine on a federal level?"

Walensky had responded: "That’s something that I think the administration is looking into. It’s something that I think we are looking to see approval of from the vaccine.

CDC DIRECTOR TELLS BRET BAIER GOVERNMENT ‘LOOKING INTO’ POTENTIAL COVID-19 VACCINE MANDATE

"Overall, I think in general, I am all for more vaccination. But I have nothing further to say on that except that we are looking into those policies."

On Wednesday, officials in New York City criticized the CDC for not releasing scientific reports or other data to justify a change in mask guidance that the federal agency issued Tuesday. 

U.S. Rep. Peter Meijer, R-Mich., also criticized the CDC on Wednesday for a lack of transparency.

"I think a lot of the frustration is coming with just the blanket absorption of CDC guidance that shifted based upon what they're citing as two unpublished studies that by virtue of being unpublished no one else can look at," Meijer said. The congressman also noted the CDC was citing "a third study from India that was based off of delta transmissibility among individuals who had a non-U.S. vaccine."

"I think a lot of the frustration is coming with just the blanket absorption of CDC guidance that shifted based upon what they're citing as two unpublished studies."

— U.S. Rep. Peter Meijer, R-Mich.

U.S. Rep. Peter Meijer, R-Mich. (Associated Press)

On Friday, following the criticism, the CDC released information that it said had informed its decision on face coverings.

It included a study of a July 3 coronavirus outbreak in Provincetown, Mass., in which more than 400 people were infected. The study found that three-quarters of those contracting the virus had previously been fully vaccinated, NPR reported.

STOCKS SLIDE AS CDC REVERSES MASK RECOMMENDATIONS

The CDC said the discovery that fully vaccinated people could spread the virus prompted its Tuesday decision to change its mask guidance.

"This finding is concerning and was a pivotal discovery leading to CDC's updated mask recommendation. The masking recommendation was updated to ensure the vaccinated public would not unknowingly transmit virus to others, including their unvaccinated or immunocompromised loved ones," Walensky said in a statement Friday.

Prior to the Friday data release, the CDC’s communications on mask guidance also drew criticism from CNN medical analyst Dr. Jonathan Reiner, The New York Times, former Food and Drug Administration (FDA) commissioner Scott Gottlieb and journalist Glenn Greenwald.

"I think the guidance is right, but I think their messaging is awful," Reiner had said during an appearance on CNN.

"I think the guidance is right, but I think their messaging is awful." 

— Dr. Jonathan Reiner, CNN medical analyst

CLICK HERE TO GET THE FOX NEWS APP

The New York Times had referred to the CDC’s messaging as "confusing," and written that the agency had "both a polarization problem and a communication problem." 

"You know there's a problem," Greenwald said, when "authority-revering CNN is starting to notice and say that the CDC's manic shifts in guidance don't seem to make sense."

Walensky, 52, became the CDC’s 19th director on Jan. 20, when the Biden administration took office. She was previously head of the infectious diseases team at Massachusetts General Hospital in Boston and a professor at Harvard Medical School.

Her appointment to the CDC did not require U.S. Senate approval.

Fox News’ Charles Creitz, Tyler Olson and Brandon Gillespie contributed to this story.