The spike in coronavirus cases in Melbourne is showing a "worrying trajectory" but South Australia is yet to make a decision to delay the lifting of border restrictions for people travelling from Victoria.
Premier Steven Marshall says local officials need more data and more evidence before making a final call on scrapping measures which require Victorians to quarantine for two weeks when they come into SA.
SA has already lifted those restrictions in relation to Queensland, Western Australia, Tasmania and the Northern Territory and is due to do the same for Victoria and NSW on July 20.
Mr Marshall says that date is subject to change, taking into account the spike in cases in Victoria with 33 new infections reported there on Thursday.
"Yes, there is a worrying trajectory at the moment," he said.
"But don't forget those sort of numbers relate to restrictions and protocols that were in place several weeks ago."
The premier said since then measures had been taken to help quell the spread of COVID-19 in Melbourne and it would take some time before the success of those changes could be determined.
"We're still hopeful we can lift our borders on the 20th of July nationwide. That was the commitment we made." Mr Marshall said.
"But we also said we are not going to lift the restrictions if it puts undue pressure on our health services.
"We are not going to be lifting the borders if it's going to set us back in South Australia.".
The premier also revealed SA is helping Victoria ramp up its testing regime with some samples being brought to Adelaide to be analysed.
He said after increasing its testing facilities in recent months, the state currently has excess capacity.
SA conducted 1688 tests on Wednesday but has not reported a new coronavirus infection for about a month.