The leaders of the Group of Seven industrialized countries are expected to pledge during the upcoming summit meeting to provide at least 1 billion coronavirus vaccine doses to the world in an effort to end the pandemic in 2022, the British government said Thursday.

The announcement came as British Prime Minister Boris Johnson, who will chair the three-day gathering from Friday, is calling on his counterparts to make "concrete commitments" to vaccinate the entire world over the next two years.

Calls have been growing for the club of wealthy nations -- Britain, Canada, France, Germany, Italy, Japan and the United States, plus the European Union -- to cooperate in helping provide vaccine access to poorer nations, as many of them have fallen behind developed countries in inoculation efforts.

Low-income nations have received less than 1 percent of vaccines administered so far, the World Health Organization, the International Monetary Fund and others warned earlier this month, noting that bringing a quicker end to the pandemic in the developing world would also accelerate global economic recovery.

According to Britain, the 1 billion vaccine doses will be provided through dose-sharing and financing, although the breakdown of contributions by donor was not immediately clear. The Associated Press reported that half of the estimated total will come from the United States.

For its part, Britain said it will donate at least 100 million surplus vaccine doses within the next year, including 5 million doses beginning in the coming weeks primarily for use in the world's poorest countries.

U.S. President Joe Biden also announced Thursday that his country will purchase 500 million doses of vaccine developed by American pharmaceutical giant Pfizer Inc. and donate them to 100 low-income countries in the world through the first half of 2022.

The Biden administration also pledged earlier to share 80 million vaccine doses from the U.S. supply by the end of June.

According to the WHO, around 874 million people in the world have received at least one dose of a vaccine against the novel coronavirus as of Thursday. The world's population is currently about 7.8 billion, data from the U.S. Census Bureau shows.