Canberra-South Australia travel bubble would show domestic travel can be safe: Andrew Barr

But a decision on whether to allow travel between ACT, NSW and South Australia is not expected until at least next week.

Chief Minister Andrew Barr is pushing separately for a bubble between the ACT and South Australia, where only Canberra residents would be permitted to fly to Adelaide.

South Australia Premier Steven Marshall has not publicly addressed the proposal, but Mr Barr says he has kept in close contact with him.

"We both know that this is an opportunity for two cities that have done extraordinarily well during the pandemic to work together to demonstrate that you can do domestic travel in a safe way," Mr Barr said.

"This will be an important first step in reopening the domestic aviation market in this country between jurisdictions that had closed borders.

"We could and should be one of the very first to move on this and that's going to be important for Canberra.

"What we're saying is COVID-safe cities can have COVID-safe travel between them."

While the ACT has not had a case of coronavirus for months, states are concerned about the free travel of residents between the ACT and NSW.

To temper those fears, the ACT has proposed identification checks are made at both Canberra and Adelaide airport to confirm the travellers are not NSW residents.

"If there was a risk of Sydney transmission being brought into Canberra, either by Sydney people coming here or Canberrans going to Sydney and bringing it back with them, if that was a rampant risk we would have seen it time and time again over the last six months," Mr Barr said.

"But it hasn't occurred.

"That's credit in part to NSW contact tracing and testing but I think credit is due in large part to the way Canberrans have behaved throughout the pandemic.

"Part of this is proving you can do it and that then being a working model as we head into Christmas.

"The onus really is on Canberra and Adelaide to prove you can make it work."

Mr Marshall on Monday said he hoped South Australia would be open to NSW and the ACT very soon.

But he said the earliest a decision could be reached was early next week.

South Australia wants NSW to record 14 days without community transmission - where cases cannot be linked to a known case or outbreak - before opening the borders.

"I don't think it will be this week," Mr Marshall said.

NSW on Monday recorded four new cases of coronavirus - one a returned traveller and three in healthcare workers at Liverpool and Concord hospitals.