A ban on Australian citizens travelling overseas will come into force at midday today.
The ban was announced last night, along with more restrictions on social interactions.
They include limiting the number of people who can attend funerals and weddings, and closing personal services such as beauty salons.
Health Minister Greg Hunt said the actions were needed to slow the spread of the coronavirus outbreak.
"There is a ban as of midday today for Australians leaving the country, other than for essential or compassionate grounds," he said.
Australian citizens who are permanent residents overseas will be exempt.
There will also be exemptions for travel that is essential, in the national interest or on humanitarian or compassionate grounds.
Australian Border Force will determine if people are eligible to travel.
"No-one should be getting on a plane and going overseas," Prime Minister Scott Morrison said on Tuesday night.
"We have been making the point for some time."
Australia has more than 2,000 cases of COVID-19.
