More than half of Australia's population will be in lockdown until at least next week with a highly infectious coronavirus strain spreading in three major capital cities.
South Australia will enter a one-week shutdown from Tuesday evening after five cases of the Delta variant were detected in Adelaide.
Victoria will spend at least another seven days in lockdown, which has been extended until next Wednesday, after nine new local cases emerged.
Crossing the NSW border into Victoria will be restricted to authorised workers and people approved on compassionate grounds.
NSW recorded 78 new local cases with 29 spending part or all of their infectious period in the community.
Experts are warning lockdown in Sydney and surrounding regions will likely stretch into August as the virus circulates in Australia's biggest city.
There will be more than 13.5 million people in lockdown nationwide when SA's restrictions come into force at 6pm on Tuesday.
Federal Health Minister Greg Hunt said Australia was in a better place to navigate the outbreaks than last year's Victorian second wave.
"These are difficult decisions, but understandable and decisions we recognise as necessary," he told reporters in Melbourne.
Mr Hunt said the NSW outbreak had stabilised with daily case numbers falling below 100.
Chief Medical Officer Paul Kelly and the expert medical panel is considering making South Australia a coronavirus hot spot.
The federal government continues to cop criticism for its sluggish vaccine rollout which has fully immunised 14 per cent of people aged over 16.
"The fact that we're losing that race compared with other developed countries is the reason why half of Australia is locked down today," Labor leader Anthony Albanese told reporters in Launceston.
Mr Hunt said he had worked behind the scenes to bring forward the delivery of three million doses from the last quarter of the year to the third.
"Every week we are fighting to bring forward additional vaccines and additional doses," he said.
The Morrison government is resisting calls to reinstate a wider wage subsidy program with millions of people under financial pressure because of lockdowns.
People in hot spots who lose work can access weekly payments of between $375 and $600 depending on whether they are part-time or full-time employees.
In NSW, 388,000 claims worth $186 million have been approved, while 58,000 Victorians have accessed grants worth $26 million.
"The money is actually flowing out the door faster than it would have under JobKeeper," Mr Hunt said.
The Australian Council of Social Service estimates 800,000 welfare recipients who support 400,000 children have been excluded.
ACOSS chief executive Cassandra Goldie is urging state and federal leaders to fill the gap ahead of a national cabinet meeting on Friday.
Mr Hunt also revealed there had been 408 cases of influenza and no deaths from it this year because of coronavirus containment measures.
By this stage, in an average year Australia would have recorded 53,000 flu cases and 157 deaths.