Dealing with the spike in cases in Victoria is top of the agenda for the national cabinet’s meeting on Friday.

States have ramped up testing and strict border controls in a bid to halt infections.

Victoria recorded 165 of Australia’s 182 new cases of the disease on Thursday, with the source of 135 under investigation.

Four new cases linked to the Melbourne outbreaks have been detected in Canberra in two days, ending the ACT’s month-long clean bill of health.

Of other new cases in NSW and WA, all but two were among returned travellers in hotel quarantine.

Health officials were tasked earlier in the week with examining quarantine arrangements in different states after the outbreak in Melbourne was linked to infection control breaches among hotel security.

The national cabinet jointly decided in late March to require quarantine for travellers from overseas, but arrangements were managed individually by each jurisdiction.

Leaders will also consider a proposal from Prime Minister Scott Morrison to cap international arrivals to ease the pressure on quarantine arrangements.

Flights to Melbourne have stopped for the time being.

In June, about 28,000 people arrived in Australia, with just over half spending their isolation period in Sydney hotels.

Melbourne and Brisbane each took about 5000.

Health officials are now recommending people in greater Melbourne and Mitchell Shire to the city’s north wear a face mask outside the home in situations where they cannot practice social distancing.

“It continues to be the case that the most important measure that you can do to prevent the virus from getting from one person to another is to maintain your distance between individuals,” Deputy Chief Medical Officer Nick Coatsworth said.

“That is the purpose of the stage three restrictions, it is why they are going to work.”

Masks are still not recommended in any other state or territory, outside of Victoria, where there is no community transmission.

-AAP