PM 'reasonably confident' SA can emerge from lockdown in six days

Prime Minister Scott Morrison says he is "reasonably confident" South Australia will be able to emerge from its harsh lockdown in six days.

South Australia has entered its six-day 'circuit-breaker' lockdown, closing all schools and forcing people to stay inside in a bid to stop its second wave of coronavirus.

Mr Morrison told Today he supported South Australia's decision to lockdown hard and early.

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"This was intended as a precaution, to ensure that what we have seen occur in the last couple of days, we could stay ahead of that," Mr Morrison said.

"They have thousands of people who have gone into isolation, they have reacted very quickly, the testing, the tracing all of that is operating and operating well.

"This should see us a move through the next few days and hopefully return to the situation that it was. I'm confident about it."

Mr Morrison said a hotspot policy was a "good mode" to follow when it came to the closure of state borders.

"South Australia has dealt with its own border issue by treating itself as a hotspot and cutting itself off for a few days," he said.

"Northern Territory has had a hotspot policy running for many months.

"They will list places for a short period of time then take those restrictions off. NSW has pushed through."

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Mr Morrison warned the possible new strain of the virus meant the state had to be "especially cautious".

"There is some uncertainties in terms of how the virus is operating there," he said.

"The suggestion of another strand, or strain ... so this needs to be got on top of.

"That will avoid a much longer lockdown, as we've had seen sadly in other states.

"So I understand the decision that's been taken. We are giving them all the support that we can."

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