Japan doubles vaccine donation pledge

Japan will double its COVID-19 vaccine donations to about 60 million doses intended for needy countries, Prime Minister Yoshihide Suga says.

The pledge adds to a previous agreement to provide 30 million doses and $US1 billion ($A1.4 billion) to the COVAX program, overseen by the GAVI alliance and the World Health Organization.

COVAX is aiming to provide global equitable access to COVID-19 vaccines.

"Japan has provided approximately 23 million doses of COVID vaccine to various countries and regions across the world, which is the third largest provision of vaccine in the world so far," Suga, who recently confirmed he would not stand for re-election, told a virtual conference on Thursday.

Japan's ruling Liberal Democratic Party is scheduled to hold a leadership vote on September 29 to decide on Suga's replacement.

Much of Japan's vaccine donations thus far have been via bilateral agreements with Asian neighbours, outside of the COVAX program.

Tokyo is giving away most of its domestically produced supply of the vaccine developed by AstraZeneca.

The nation has relied mainly on imported mRNA-type vaccines from Pfizer and Moderna for its inoculation push, which has fully vaccinated about 55 per cent of its population, according to government data.