President Joe Biden on Wednesday announced that the U.S. would commit to buying another 500 million doses of Pfizer's COVID-19 vaccine to share with low- and middle-income countries by next year.

The additional 500 million vaccine doses doubled previous U.S. commitments to a grand total of 1.1 billion doses between this summer and next year.

"To beat the pandemic here, we need to beat it everywhere," Biden said in making the announcement at the virtual summit on COVID-19 on the sidelines of the UN General Assembly.

Biden also announced that the U.S. is embracing a global goal of having 70% of the world's population vaccinated within the next year. He also pushed for other wealthy nations to make similar commitments.

"We're not going to solve this crisis with health measures or middle-of-the-road initiatives," Biden said.

In June, during an event at the G7 Summit, Biden announced his intention to purchase and distribute 500 million doses of the Pfizer vaccine. The White House has already begun shipping the first 200 million doses of that commitment, and the remaining 300 million doses will be donated in early 2022.

At the same event in June, the other G7 nations agreed to purchase an additional 500 million doses.