Australia has pledged to send 60 million coronavirus vaccine doses to countries across the Indo-Pacific region by the end of next year.
Prime Minister Scott Morrison on Thursday announced a commitment for an additional 20 million doses during US President Joe Biden's COVID-19 summit.
Australia will also procure a further 20 million on top of the same amount Mr Morrison promised in June.
"That's up to 60 million vaccine doses for our region, between now and the end of 2022," he told world leaders.
More than 3.2 million doses have been delivered under the initial pledge.
The prime minister said Australia's commitments would have no strings attached.
"No country is safe until we are all safe," he said.
"That's why it's vital we work together. To save lives and livelihoods; to rebuild what we've lost."
Reverend Tim Costello, who leads the End COVID For All campaign, welcomed the announcement but called for more on-the-ground rollout support.
Mr Costello said contributing to global efforts like the COVAX facility would be the world's best chance to stop the virus mutating while it decimated low-income nations.
"If we don't act to fight COVID everywhere, experts estimate it could take less than a year before the virus mutates to the point where the majority of first-generation vaccines are rendered ineffective," he said.
He called for Australia to spend an additional $250 million on COVAX and $50 million on addressing vaccine hesitancy around the world.
Mr Morrison said the government had committed $623.2 million to support neighbours' rollouts and provide vaccines.
He said 4000 ventilators, almost 2000 oxygen concentrators, and 106 tonnes of protective gear and medical equipment had been supplied to the Indo-Pacific.
Indian Prime Minister Narendra Modi also addressed the White House summit, noting his country had shared vaccines with 95 other nations and United Nations peacekeepers.
"With our Quad partners, we are leveraging India's manufacturing strengths to produce vaccines for the Indo-Pacific region," he said.
India and South Africa have proposed an intellectual property waiver for vaccines, diagnostics and medicines.
"This will enable rapid scaling up of the fight against the pandemic. We also need to focus on addressing the pandemic economic effects," Mr Modi said.
"To that end, international travel should be made easier, through mutual recognition of vaccine certificates."
India, which is running one of the world's biggest vaccination programs, recently administered 25 million doses in a single day, equivalent to Australia's population.
Meanwhile, the United Kingdom has almost completed delivering four million Pfizer doses to Australia under a vaccine swap deal.
"We will have them returned when your stock and supplies have been built up," UK High Commissioner to Australia Vicki Treadell told Sky News.
"We're ready for those hopefully around November."
Australian Associated Press
