Australia Prime Minister Scott Morrison has announced that all overseas arrivals to Australia will be required to self-isolate as the country tackles the coronavirus pandemic.

Photo: AFP

Australia has recorded more than 250 coronavirus cases and three deaths.

The new restrictions will come in from midnight tonight.

Morrison has introduced measures similar to New Zealand when it comes to overseas arrivals.

He announced the measures late this afternoon after a meeting with a newly formed national cabinet, dubbed the coronavirus 'war cabinet'.

"To help stay ahead of this curve [of an increase in Covid-19 cases], we will impose a universal self-isolation requirement on all arrivals to Australia and it is effective from midnight tonight.

"All people coming to Australia will be required, I stress, to self-isolate for 14 days. This is very important. "

The Australian government has also banned all cruise ships from foreign ports from visiting Australia for the next 30 days.

Photo: AFP

Australia has already imposed bans for travellers from Italy, South Korea, Iran and China, countries with high infection rates.

The bans mean foreign nationals who have been in any of the four nations will not be allowed into Australia for 14 days from the time they left those countries.

Australian citizens and permanent residents travelling from those countries will still be able to enter Australia but must self-isolate for a fortnight after returning home.

Australia has advised against non-essential gatherings of more than 500 people from Monday, but this is yet to apply to schools and universities.

It has also endorsed health experts' advice on "social distancing" - not shaking hands or getting within a metre of another person.

Morrison said the rate of community transmission had started to increase and that social distancing would help limit demand on the healthcare systems, which would mean better treatment for the elderly and those in remote and vulnerable communities.

"Slowing the spread will free up beds," he said. "That's what happens when you get this right and we've seen other countries going down this path."

Schools will remain open

Morrison said schools will stay open and he recognised that while parents are anxious about students picking up coronavirus in the classroom, the advice that he has received is that they should remain open for now.

He said children would engage more with others in the community if they weren't at school.

"Our other issue is ... [it] puts a greater risk on nurses and doctors essential in the community, because they would have to remain home and look after their children."

He said the latest government measures were aimed at slowing the risk, especially for the most vulnerable - the elderly and those with underlying health conditions.

The new phase of restrictions come as the Australian government launches a multi-million-dollar advertising campaign focused on good hygiene, and the formation of a Coronavirus Business Liaison Unit to address the economic fallout.

Meanwhile, another 22 people in New South Wales have been infected with coronavirus.

The Department of Health says among the new cases are four people who have travelled from the United States.

It's the single largest jump in confirmed cases so far in NSW, taking the state total to 134.

NSW Health authorities say they can't work out the source of 10 of the new cases.

- ABC / Reuters