States and territories are now considering, following a national cabinet meeting on Sunday, whether to make the two-person limit enforceable.
The limit will not apply to households, education or employment, while skate parks and public playgrounds will also be closed.
Asked how it would apply to a family, Prime Minister Scott Morrison said parents and children could go for a walk together even if there were more than two.
Morrison also announced all people aged 70 and over should stay at home and self-isolate for their own protection.
“They are not self-isolating for the purpose that people … but this is for their own protection to limit their interaction with others in the community,” he said.
“This does not mean they cannot go outside. They can go outside and be accompanied by a support person for the purposes of getting fresh air and recreation but should limit contact with others as much as possible. ”
He said all Australians should remain at home except for a number of reasons.
These included shopping for food and other essential items, medical care, compassionate needs, exercise and work or education if remote working or learning is not available.
As well, people aged over 60 with chronic illness and indigenous people over the age of 50 should self-isolate as much as possible.
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