Australia has fallen 3.4 million doses short of its target of delivering four million Covid vaccinations by 31 March, prompting criticism of the government.
The 85% shortfall comes two days after Brisbane entered another snap lockdown to combat a small outbreak.
Last week the government said the vaccine rollout did not demand urgency given Australia's low infection rates.
The country has recorded 909 deaths and 29,300 cases since the pandemic began - far fewer than many other nations.
But sporadic outbreaks have led to six lockdowns in cities in recent months. Critics say situations like Brisbane's outbreak show why a quick vaccine program is still needed.
Brisbane's two clusters have been linked to a nurse and a doctor who contracted the virus from a Covid ward at the same hospital.
It's unclear why those health workers had not yet been vaccinated, officials said.
