The US Food and Drug Administration on Monday gave full approval to the COVID-19 vaccine made by Pfizer and German partner BioNTech for use in people over the age of 16.
It's the first such approval of a COVID-19 shot.
The vaccine has been authorised for emergency use since December and more than 204 million people in the United States have received it, based on Sunday's data.
But none of the three authorised COVID-19 vaccines had previously received full FDA approval.
Public health officials hope it will convince more unvaccinated Americans that Pfizer's shot is safe and effective.
Vaccine hesitancy among some Americans has hindered the United States response to the novel coronavirus.
"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," said Janet Woodcock, the US Food and Drug Administration's acting commissioner.
Roughly 51 per cent of Americans have been fully vaccinated so far, even as a recent surge of infections spurred by the contagious Delta variant ravages parts of the country with low vaccination rates.
Israeli planes and tanks pounded areas across the Gaza Strip overnight and on Sunday, destroying several residential buildings, witnesses said, as Palestinians desperately awaited implementation of a US plan to end the war.
The number of students confirmed dead after the collapse of a boarding school building in Indonesia rose to 36, from 16 a day earlier, the country's disaster mitigation agency said on Sunday.
Russia rained missiles and drones on Ukraine in a mass overnight attack, officials said on Sunday, killing at least five people and damaging civilian infrastructure including energy facilities across numerous regions.
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