President Joe Biden says his administration will meet his goal of administering 100 million vaccine shots on Friday - six weeks ahead of schedule.
"I'm proud to announce that tomorrow, 58 days into our administration, we will have met our goal," he said on Thursday.
"That's weeks ahead of schedule, even with the setbacks we face during the winter storms, and another big step on the path to putting cheques in pockets and shots in people's arms. "
The president's original target had been to reach that milestone after 100 days in office. It was announced on 8 December, before the US had even one authorised vaccine for COVID-19.
By the time Mr Biden was inaugurated on 20 January, the US had already administered 20 million shots at a rate of about one million doses per day.
At the time, that rate led to complaints that his goal was not ambitious enough.
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He quickly revised it upwards to 150 million doses in his first 100 days.
Now the US is administering about 2.2 million doses a day and the pace of vaccination is set to dramatically rise later this month because of an expected surge in vaccine supply.
A total of 65% of Americans who are 65 years and older have now received at least one shot of a COVID-19 vaccine.
Since taking office, the Biden administration has worked to ramp up the supply of vaccine doses in the US after states complained that demand for the shots was outpacing supply.
Last week he said that all American adults would be eligible for a vaccine by 1 May.
Almost 530,000 Americans have died from coronavirus over the past year - and millions more have fallen ill.
