(CNN) For two years, Australia avoided the worst of the coronavirus pandemic thanks to strict border controls and prolonged lockdowns.
But Covid cases are now rising rapidly in the country, with the Omicron variant posing a new threat just as states and cities were beginning to loosen restrictions.
On Tuesday, the country's most populous state reported its highest new daily caseload of the pandemic, and Australian Prime Minister Scott Morrison called an emergency National Cabinet meeting to discuss the rising infections.
But he said one key message he'll be telling state premiers is a return to lockdowns, tight social restrictions and fines for violating them is not the answer.
"We have got to get past the heavy hand of government and we've got to treat Australians as adults," Morrison said at a news conference in Queensland Tuesday. "We have to move from a culture of mandates to a culture of responsibility. That's how we live with the virus into the future."
His comments come as New South Wales reported 3,057 cases in the 24 hours to 8 p.m. local time Monday -- a record for daily infections in the country. A total of 284 people are hospitalized with Covid-19 in the state, with 39 patients in intensive care. Long queues formed outside testing centers as thousands of people complied with orders to take a test ahead of the holiday.
Meanwhile, Queensland state health authorities warned Tuesday they are seeing a doubling in cases every two days -- a growing number of which are the Omicron variant -- but said they will move forward with easing quarantine restrictions.
The rise in infections in Australia comes as countries across much of the Asia-Pacific region are delaying their reopening plans, with some reimposing restrictions or tightening border controls over Omicron concerns.
The World Health Organization said on Monday that Omicron is spreading "significantly faster" than the Delta variant and is causing infections in people who have been vaccinated or have recovered from Covid-19. But scientists still don't know for sure if the variant causes more severe disease or to what extent existing vaccines are less effective against it.
NSW Premier Dominic Perrottet echoed Prime Minister Morrison's words in an op-ed for Australia's Daily Telegraph on Monday, despite the rising cases in his state.
"One of the most powerful reflexes is the feeling that with every new case, we should lock everything down," Perrottet said. "But this is not December 2019, and since the virus first emerged, one thing above all else has changed the game: vaccination."
The premier said if the trajectory of an outbreak threatens to overwhelm health services the state will change its approach, but "it is time to shift the balance back to personal responsibility."
"NSW is resilient. Our people are strong. This is our moment to stand tall and lead the nation out of this pandemic," Perrottet said.
In Australia, 90.6% of people age 16 and over have been double vaccinated, according to the Department of Health. But while vaccination is a key pillar in the country's Covid response, a growing divide appears to have opened between the government and health experts since the emergence of Omicron.
The president of the Australian Medical Association, Dr Omar Khorshid said the "reckless" approach adopted by Perrottet was putting lives at risk.
"DIY contact tracing, watered-down check in requirements, the abandonment of mask wearing mandates, and the removal of density limits are together a recipe for disaster and by the time hospital admissions and ICU cases grow beyond whatever benchmark he is working to -- it will be too late," Khorshid said in a statement.
Dan Suan, a researcher and clinical immunologist from Sydney's Garvan Institute of Medical Research, said in a 17-minute Facebook video posted on Sunday that if Sydney residents don't change their behavior in the run up to Christmas, the city could be "sleepwalking into a catastrophic disaster in January."
"Virtually everybody can catch Omicron. We risk turning Christmas day into a simultaneous super spreader event all across Sydney in thousands of households," Suan said in the video.
"If everybody catches Omicron on Christmas Day, then there will be a hospital-based disaster by early January because all the infections happen at the same time. And we know what happens when a huge number of people attempt to try to get a hospital bed at the same time. They can't get the care that they need. And the death toll starts to climb far higher than it should," he said.
Last week, NSW Health Minister Brad Hazzard warned that, based on current modeling, the state could record up to 25,000 new infections a day by the end of January.
Across Asia-Pacific, Omicron is forcing countries to rethink loosening their restrictions.
In South Korea, serious Covid infections are reaching record highs and the country's President Moon Jae-in has ordered national university hospitals to focus on treating critically ill Covid-19 patients.
Moon told public hospitals in the greater Seoul area to shift specialization to infectious diseases where possible, called for an expansion of hospital beds for treating Covid-19 patients and said military doctors should be assigned to treat seriously ill Covid patients.
On Sunday, South Korea reported a record 1,025 critically ill Covid-19 patients. The number slightly dropped to 997 on Monday, according to the Korea Disease Control and Prevention Agency (KDCA).
Last week, the government reversed its phased plan to ease restrictions and instead reinstated stringent social distancing measures, including a 9 p.m. curfew nationwide for restaurant and cafes.
On Tuesday, New Zealand said it will push back its phased border reopening until the end of February over Omicron concerns. The measures were expected to begin as early as January.
And last week, Malaysia announced new Covid-19 measures, including banning mass gatherings and requiring booster doses for high-risk groups as it reported its second case of the Omicron variant, according to Reuters.