(CNN)President Joe Biden will unveil a $2 billion U.S. contribution to a global coronavirus vaccine initiative when he speaks with the leaders of the world's leading market economies on Friday, according to senior administration officials, boosting efforts to distribute shots to low- and middle-income countries as wealthier nations snap up the limited supply.

The U.S. plans to commit an initial $2 billion to Gavi and an additional $2 billion through 2021 and 2022.

There has been pressure on Biden to donate a percentage of the USA vaccine allotment to poorer countries, including from France's Emmanuel Macron.

COVAX hopes to provide vaccinations to at least 20% of the population in 92 of the world's poorest countries by the end of this year. Trump declined to participate in the global effort, insisting his focus must be on providing shots to Americans.

Although the United States is "prioritising" domestic needs, assistance to other countries "decreases the risk to everyone in the world, including Americans, and also decreases the risk of variants", the official said.

He said the vaccine will be used to start a public vaccination programme for people above the age of 60.

That is likely to mean the USA will have ample surplus doses that could be donated to poorer nations.

There are calls for an allocation of national vaccine supplies to be given to developing countries

"When we have a sufficient supply, it's our intention to consider donating surplus vaccines", one of the officials said.

The U.S. officials said the donations would not interfere with Biden's promise to have enough vaccines available for all Americans who want them by the end of July.

In an interview with Britain's Financial Times, French President Emmanuel Macron called on the United States and European nations to allocate up to 5 per cent of current vaccine supplies to developing countries - the kind of vaccine diplomacy that China and Russian Federation have begun deploying.

"This huge excess is the embodiment of vaccine nationalism", said Jenny Ottenhoff, ONE Campaign's senior director for policy.

According to Roque, the Philippines has complied with the above requirements as the Philippine Food and Drug Administration has already issued an EUA for the vaccines from Pfizer and AstraZeneca; the indemnity agreed has been submitted by Secretary Galvez and that the country has already submitted the national vaccine plan. The plans are required for countries to receive vaccines from COVAX, the global initiative to ensure fair access to COVID-19 vaccines led by WHO, Gavi, the Vaccine Alliance, and The Coalition for Epidemic Preparedness Innovations (CEPI).

He said the global community needs to continue to unite and strengthen multilateral cooperation to effectively coordinate joint efforts on pandemic prevention, affirming Vietnam would continue to contribute its best to the joint efforts to overcome the pandemic.

"Certainly we've seen attempts by other countries - China and Russian Federation - to use vaccines as a means of making progress diplomatically", White House press secretary Jen Psaki said. "But we are - we watch those actions with concern".