Australia has secured an additional 20 million Pfizer coronavirus vaccines, doubling the amount of doses set to arrive in the country this year.
Prime Minister Scott Morrison welcomed the supply boost after the government backed health advice to avoid people under 50 receiving the AstraZeneca jab because of extremely rare blood clots.
The deal means 40 million Pfizer doses, enough for 20 million people, are due to be shipped to Australia in 2021.
Less than one million doses have so far arrived in the country, with supply issues hampering the speed of the rollout.
Pfizer jabs have become far more crucial following the advice around AstraZeneca, which was going to be administered to most Australians.
The extra doses are due to arrive in the final three months of 2020.
Australia broke the one million-dose barrier on Friday - a week after the date the government had committed to administering four million jabs.
Health Minister Greg Hunt said more than 81,000 shots were given in the past 24 hours, the highest daily increase since the program started in late February.