The US Food and Drug Administration (FDA) on Monday granted full approval to Pfizer-BioNTech's COVID-19 vaccine for people 16 and older, a move that is expected to pave the way for public and private entities to mandate vaccinations and help persuade hesitant Americans to be more receptive to getting vaccinated.

"Today marks a key milestone in our nation's fight against COVID," President Joe Biden said after the approval was announced. "Those who have been waiting for full approval should go get your shots now. The vaccination is free, it's easy, it's safe, it's effective, and it's convenient."

Biden said that 90 percent of Americans can get the vaccination within 5 miles of their homes without an appointment. He said that the Delta variant is dangerous and spreading, especially among the unvaccinated.

Vaccination is working, Biden said. "Even though the Delta variant is ravaging the unvaccinated, the death rate is 70 percent lower than in last winter," he declared.

Pfizer's vaccine was first approved for emergency use in December last year. It continues to be available under emergency use authorization for young people 12 through 15 years old and for the administration of a third booster shot for immunocompromised individuals.

Pfizer plans to market the vaccine under the name Comirnaty. It took the FDA less than four months to grant Pfizer the approval while the normal timeframe is about 10 months.

"The public and medical community can be confident that although we approved this vaccine expeditiously, it was fully in keeping with our existing high standards for vaccines in the US," said Peter Marks, director of the FDA's Center for Biologics Evaluation and Research.

The FDA analyzed effectiveness data from approximately 20,000 vaccine recipients and 20,000 placebo recipients ages 16 and older. Based on results from the clinical trial, the vaccine was 91 percent effective in preventing COVID-19.

"While millions of people have already safely received COVID-19 vaccines, we recognize that for some, the FDA approval of a vaccine may now instill additional confidence to get vaccinated," Dr Janet Woodcock, the acting FDA commissioner, said in a statement. "Today's milestone puts us one step closer to altering the course of this pandemic in the US."

Pfizer plans to request booster authorization as well as full approval for young people age 12-15. Moderna, whose vaccine under emergency use authorization adopts similar mRNA technology, is in the process of completing data submission for its request for full approval. Johnson & Johnson plans to file for full approval later.