South Australia has reported its first new cases of coronavirus for a month with three infections detected among Australians who flew home from India on the weekend.
SA Health says a three-year-old girl and two women, one in her 30s and one in her 40s, have tested positive after flying in from Mumbai on Saturday.
Chief Public Health Officer Nicola Spurrier says the cases do not come as a surprise considering the high rate of infections on the sub-continent.
Professor Spurrier said all three remained in supervised quarantine and were experiencing either none or very mild symptoms.
About 260 people arrived on the flight from India while up to 100 defence force personnel were also flown in from Butterworth in Malaysia.
None of the defence force personnel tested positive for COVID-19.
The three new infections are SA's only active cases. The state has had a total of 443 cases.
They also come amid growing concerns around the spike of cases in Melbourne which has left SA's plans to lift border restrictions with Victoria in doubt.
Premier Steven Marshall has insisted SA won't lift quarantine requirements for anyone arriving from Victoria if it is not safe to do so.
Under current arrangements, those measures are due to be scrapped on July 20.
"So we've still got three weeks, but that is now under a cloud," the premier said on Monday.
"We will look very closely at this and update the people of South Australia as soon as we possibly can.
"We are very concerned about the numbers coming out of Victoria at the moment, there's no doubt about that."
Victoria reported 75 coronavirus cases on Monday after revealing 90 new infections over the weekend.
Police Commissioner Grant Stevens said he would take advice from the experts in SA Health in relation to the efforts in Victoria to contain the virus and to properly establish the extent of the spread into the Victorian community.
"The reality is, the numbers we're seeing today relate to activities that occurred over the last two weeks, so we may see a much better performance from Victoria over the next few days," Mr Stevens said.
"It's important to everybody that Victoria gets this under control."
From Wednesday, SA is also moving to a pre-approval system for all people entering the state as part of ongoing COVID-19 restrictions.
Anyone wanting to come to SA by road or air will need to apply through an online form, a process officials say will speed up border access.
People arriving from Queensland, Western Australia, Tasmania and the Northern Territory will not be required to quarantine, but 14 days of isolation will continue for anyone from NSW, Victoria and the ACT.