South Australia will no longer lift its border restrictions with New South Wales on July 20, citing concerns about an outbreak linked to a Sydney pub which is now responsible for 21 cases of coronavirus.

Residents will still be able to enter the state, but will need to spend 14 days in hotel quarantine. Victorians are not able to enter SA at all.

Premier Steven Marshall said an outbreak at the Crossroads Hotel in Casula, western Sydney, had heightened the risk of unrestricted travel to an unacceptable level.

“We know this is going to be very inconvenient,” he said, “but our primary responsibility in South Australia is the health, safety and welfare of South Australians.”

“Of course, we don‘t want to go backwards. We know what’s happened in Victoria with the second wave, in Melbourne in particular. This has costs tens of thousands of people their jobs,” he said.

“We don’t want to be putting additional restrictions back in place in South Australia that would mean South Australians would lose their jobs.”

Mr Marshall said he was not considering a “hard” closure for NSW, like the one in place for Victorians, at the moment, and said the Transition Committee would meet again on Friday to reassess the situation.

There were no new cases in South Australia on Monday, heightening fears of infected Australians from interstate being able to roam free in SA.

Mr Marshall said he was ‘deeply concerned’ about the superspreader event at the Crossroads Hotel, and noted many truck drivers heading to South Australia with freight stopped at the venue.

Victoria recorded 270 new cases on Tuesday morning, while NSW announced 13 – with only two of those being returned travellers in quarantine.

Queensland has shut its borders to hundreds of thousands of southwest Sydney residents, declaring the Campbelltown and Liverpool local government areas – comprised of 77 suburbs – “hot spots” as of noon on Tuesday.