South Australia has moved to lift some virus restrictions for travellers from regional NSW but will keep other measures in place.

South Australia will lift COVID-19 restrictions for travellers from regional NSW but continue to block visitors from Sydney and surrounds.

The new arrangements will apply from Thursday, though people arriving from regional areas will be required to have three coronavirus tests.

The hard border arrangements for Greater Sydney, Central Coast, Blue Mountains and Wollongong regions will remain.

People from those areas are not allowed to enter SA unless they are an essential worker or have an exemption.

Premier Steven Marshall says SA will also keep its border measures in place for Greater Brisbane, with travellers from there required to quarantine for 14 days.

Mr Marshall said it was hoped more restrictions could be eased in the coming days, especially for Queenslanders.

But he said there were still some "worrying concerns".

"We don't want to go one or two days too early and then have a catastrophe on our hands," Mr Marshall said.

SA's decision came as the Queensland government moved to shut a quarantine hotel after six people staying there contracted the more virulent UK strain of coronavirus.

Chief Public Health Officer Nicola Spurrier said local officials were checking to see if any people recently released from that hotel had travelled to SA.

If so, they would be required to go into quarantine.

"We're still trying to get to the bottom of what's happened in that particular hotel," she said.

"But we do know that this is one of these new variants of concern and we know that it is more transmissible and we don't want to take any chances.

"We felt that weighing these things up it was much safer to continue as we are at the moment."

NSW reported one new local COVID-19 case, a child who was a close contact of a case linked to the 28-person Berala cluster in western Sydney.

SA reported two new coronavirus cases, both men in their 30s who recently returned from overseas.

There are now 12 active infections in South Australia, all returned travellers in quarantine.