The government has ordered 10 million more doses of the Pfizer-BioNTech coronavirus vaccine, but is still waiting for the first order to arrive.
To ensure the maximum possible vaccine protection in Australia, the government will also offer free doses to anyone in Australia, regardless of their visa status.
Visa holders, refugees, asylum seekers, temporary-protection visa holders, those on bridging visas and those whose visas have been cancelled will given free doses after the government's top health advisors made the recommendation.
Prime Minister Scott Morrison said the additional purchase brought the total doses Australia had ordered to 150 million doses, including the now 20 million from Pfizer, 53.8 million of the Oxford-AstraZeneca vaccine, and 51 million of the Novavax vaccine.
Health Minister Greg Hunt said the extra 10 million doses would arrive by the end of 2021, and told reporters he received assurances from Pfizer on Thursday morning the first doses were still on track to arrive later this month.
Mr Hunt said the additional purchase was made on advice from the top committee of government health advisors, and ensuring doses for everyone was important for protecting the whole community.
"Uptake of the vaccine is very important and the more Australians we have vaccinated, the better," Mr Hunt said.
"We considered is that we need to make sure that everybody who's on Australian soil is safe, and everybody who's on Australian soil has access to protection.
"On the advice of the medical experts, the government has determined that we will offer vaccines to all people living in Australia to achieve the maximum level of coverage."
As part of the wider communication strategy for the vaccines, the government is allocating additional $1.3 million to multicultural peak bodies, with advertising to be in 23 additional languages.
The government had previously ordered 10 million doses of the Pfizer vaccine while it was still in development, and on Thursday revealed the original contract had a clause allowing for the ordering of additional doses if the vaccine was approved by the Therapeutic Goods Administration.
Using cutting-edge mRNA technology, the Pfizer vaccine requires storage at ultra-cold temperatures of minus 70 degrees until it is thawed before administering. It requires two doses, administered at least 21 days apart, meaning the 20 million doses ordered will cover 10 million people.
Mr Morrison confirmed he would receive the Pfizer jab by the end of the month.
There have been concerns about whether global supply issues will affect Australia's ability to begin the rollout this month, and the Pfizer vaccine cannot be manufactured in Australia, as the facilities do not exist to manufacture the mRNA technology.
While the government has invested in upgrading facilities at CSL in Melbourne to increase its production capacity for the AstraZeneca vaccine, Mr Morrison said capability for the mRNA vaccine technology is "a particular challenge".
Health secretary Brendan Murphy said developing such capability was being explored by the government.
"CSL, our sovereign manufacturing company, are looking at that, the government has commissioned research to look at what potential there is, it's an active consideration matter at the moment."