Defence and foreign affairs employees being posted overseas will be among the first in line for a COVID-19 vaccine while other public service employees will maintain their position in accordance with the national rollout.
The country's national vaccine program is gearing up to begin with frontline and critical workers, along with identified vulnerable Australians, expected to receive the first doses within the week.
It comes as Health Minister Greg Hunt announced on Monday afternoon the first batch of Pfizer vaccines had arrived in the country, with the 142,000 doses to be rolled out from February 22.
A second vaccine, the AstraZeneca, is expected to be deployed to the rest of those within the first phase in early March, pending approval from medical regulator the Therapeutic Goods Administration.
Among those to receive some of the first jabs are employees, and their dependents, of the Department of Defence and Department of Foreign Affairs and Trade on overseas postings or due to be deployed on them in the coming months.
A circular from the Australian Public Service Commission, released in early February, said a separate rollout strategy was being developed to ensure the departments' capabilities were retained.
The departments did not confirm when the first vaccines would be delivered but added they would be administered once they were available within Australia.
"The [departments] are working together to ensure that all staff and their dependents overseas have access to vaccinations as soon as practicable, and before the end of 2021," a foreign affairs spokesperson said.
Other public service staff would receive one of the vaccines in line with their demographics or the characteristics of the work they perform.
While the commission's circular said the vaccine was voluntary, though strongly recommended, for public service staff, deploying Defence personnel would have no choice but to receive it.
"As the vaccines become available in Australia, deploying ADF personnel will be required to vaccinate, as they are for other vaccinations, based on regional risk profile," a defence spokesperson said.
With the Pfizer and AstraZeneca vaccines expected to be ready in the coming weeks, Mr Hunt said the two vaccines are both expected to be distributed across the initial phases.
It's unclear whether Defence and DFAT employees will receive one vaccine or whether both will be administered depending on supply and availability. The Canberra Times has asked the Department of Health for confirmation.
Defence said the number of deployed personnel varied but publicly available figures suggest almost 1500 could be eligible to receive a vaccine in the near future.
The department added personnel already on deployments could access a vaccine in their country of posting provided it had been approved by a regulatory authority with a similar standing to the TGA.
An average of 32 officers were deployed each month by DFAT to one of its 121 postings around the world.
Dependents of the posted staff would also be added to the vaccination lineup, according to the planned strategy.