Prime Minister Scott Morrison has told Australians to cancel all non-essential travel.
He also flagged "far more draconian measures to enforce social distancing" saying too many Australians did not seem to be getting the message.
Mr Morrison had planned to consider more travel advice at a meeting of state and territory leaders on Tuesday evening, but on Sunday said the decision had been brought forward.
"After consulting with premiers and chief ministers overnight, we have decided that we are moving immediately to recommend against all non-essential travel in Australia," he said.
"All non-essential travel should be cancelled."
It comes as coronavirus cases surge. At 6.30am on Sunday, Australia had 1098 cases, up 224 cases in just one day, and up almost five-fold since last Sunday, March 15, when there were 249 cases.
The advice to cancel domestic travel will disrupt school holiday travel plans, with Australians already told not to travel overseas, and the borders already closed to arrivals of non-residents.
"It does mean that those holidays that you may have been planning to take interstate over the school holidays, cancel it," he said.
"It is regrettable and I know the impact it will have many people in those communities where those holidays were going to take place...
"That travel needs to be reduced to stop the spread of the virus across the country."
Mr Morrison also had a warning for pubs and restaurants that did not take social distancing rules seriously.
"If there have been pubs and clubs that are heaving with people on the weekend, that is simply an invitation for the states and territories to shut them down - and if they are unable to get a handle on that, than they are bringing on what would be their worst outcome," he said.
"Coronavirus is not a secret. Everybody knows. It is wall-to-wall on every coverage, and every conversation happening around this country today. And so there is no excuse to say you don't know. It is one to 1.5 metres, it is a four square metre rule. You have to keep a healthy distance between each other.
"If Australians can't do that on a broad scale, then they are denying the governments and the authorities the most important weapon we have two save lives and to save livelihoods, and states and territories will have to take more severe responses to deal with that."
Mr Morrison said parliament was also moving to "emergency mode" for six months.
It might not be physically possible to convene parliament in that time, he said.
A truncated parliament meets on Monday to pass the two tranches of stimulus payments and to pass other emergency measures.
The state and territory leaders would meet again on Sunday night to consider "far more draconian measures to enforce social distancing", Mr Morrison said.
"More stronger measures will be coming," he said.
"What happened at Bondi beach yesterday was not OK. And served as a message to federal and state leaders that too many Australians are not taking these issues seriously enough," he said.
"So the measures that we will be considering tonight means that state premiers and chief ministers may have to take far more draconian measures to enforce social distancing, particularly in areas of outbreaks."
Deputy Chief Medical officer Paul Kelly said medical care would change. Intensive care could be ramped up substantially, but authorities were also looking at "hospital in the home" and "a model of care which may look quite different to what we are used to in relation to people that are ill".
"We're doing that work right now. We have another infectious disease consultant who has joined us this week, Dr Nick Coatsworth. He is working with the Society for Respiratory Physicians as well as the Infectious Diseases Society and intensive care to do exactly that work with a view to having that all locked down and very ready to go this week," Professor Kelly said.
Dr Coatsworth is a consultant at Canberra Hospital and senior lecturer at the Australian National University.
Professor Kelly said Australia had the capacity to produce new ventilators in Australia. They were "not the ones that are generally used in intensive care but they can be adapted to do so", he said.
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