Originally Published: 23 AUG 21 13:06 ET

Updated: 23 AUG 21 14:07 ET

By Kate Sullivan, CNN

(CNN) -- President Joe Biden on Monday encouraged Americans who have been waiting for full approval from the US Food and Drug Administration to go get vaccinated against Covid-19 after the FDA approved Pfizer-BioNTech's vaccine.

"Today we've hit another milestone, a key milestone, in our nation's fight against Covid," Biden said, later reiterating a call for additional vaccine requirements in the public and private sectors.

He added, "If you are one of the millions of Americans who said they will not get the shot until it has full and final approval of the FDA, it has now happened. The moment you've been waiting for is here, it's time for you to go get your vaccination and get it today. Today."

The Pfizer/BioNTech Covid-19 vaccine is the first coronavirus vaccine to be fully approved by the FDA -- the Moderna and Johnson & Johnson Covid-19 vaccines remain under emergency use authorization -- and the announcement is expected to open the door to more vaccine mandates.

Pentagon spokesman John Kirby said during a briefing on Monday the Department of Defense would move forward with requiring all US military service members to be vaccinated now that the Pfizer/BioNTech vaccine has full FDA approval.

Also on Monday morning, New York City Mayor Bill de Blasio announced a Covid-19 vaccine mandate for all education department staff for all public schools across the city without a testing alternative, becoming the largest school system in the US to do so.

The Pfizer/BioNTech vaccine has been authorized for emergency use in the United States since mid-December for people age 16 and older. In May, the authorization was extended to those 12 and older. Out of more than 170 million people in the United States fully vaccinated against Covid-19, more than 92 million have received the Pfizer/BioNTech vaccine.

US Surgeon General Dr. Vivek Murthy said on CNN's "State of the Union" on Sunday that approval could encourage more people to get vaccinated, and more mandates.

"For businesses and universities that have been thinking about putting vaccine requirements in place in order to create safer spaces for people to work and learn, I think that this move from the FDA, when it comes, will actually help them to move forward with those kinds of plans," Murthy told CNN's Brianna Keilar.

Last month, Biden announced all federal employees must attest to being vaccinated against Covid-19 or face strict protocols including regular testing, masking, limits on official travel and other mitigation measures. Contractors working for the federal government will also be subject to the new rules.

This is a breaking story and will be updated.