Victoria is actively looking at ways to further strengthen its border closure with NSW, Premier Daniel Andrews says.
"Just in terms of the border, I'm not here today to make announcements but we are actively looking at what more we can do," Mr Andrews said.
"It's a pretty hard border now, police are using technology, drones, choppers they're doing random stops, they're doing all sorts of things, and overall compliance with the permit system has been very, very high.
"But I certainly can't rule out further changes and further limiting of movement from NSW to Victoria."
Mr Andrews said there was currently no issues with COVID within border communities.
"Not withstanding the Mildura issue, we don't have an issue along the border, that bubble is operating well and I know people in those communities take their responsibilities very seriously and want to maintain that freedom of movement..." he said.
"It's not that we have a problem in that area, in the bubble, it's more we have an issue flying over or driving through that bubble and potentially unknowingly coming to Melbourne and bringing the virus with them."
Mr Andrews said another case of COVID had been diagnosed in regional NSW which showed that the 'tough call' to declare all of NSW a red zone was correct.
He said first of all Victoria had to deal with its own cases, then they need to look at the border and what more they can do.
Mr Andrews said regional Victoria would not be released from lockdown early.
As COVID cases remain high in Sydney, Victoria faces the challenging task of defending its border with NSW, Victorian Premier Daniel Andrews has said.
"Even once this outbreak, as complex and as challenging as it is, is dealt with unless and until case number in Sydney dramatically reduce, we're going to have an ongoing challenge in terms of deafening that border to the north and making sure no one who has this virus is coming to our state," Mr Andrews said.
"That's for another day... that's principally our challenge but we will be calling on the community to play their part in that for a lengthy period in time, that's just a reality we face.
"I'm confident we will face that reality open as opposed to closed which is where Sydney finds itself now and for the foreseeable future. We wish them well..."
Mr Andrews said if NSW has a problem the whole country has a problem.
Chief Health Officer Brett Sutton said these were "profoundly challenging times."
"We have to win, we have to extinguish it," he said of the Delta variant.
Mr Andrews said four additional cases have been recorded so far today, all four were in isolation during their infectious period.
Mr Sutton said there was no doubt more cases would be recorded today.
Victoria's snap lockdown has been extended as Premier Daniel Andrews revealed only one of the 13 new cases were in isolation while infectious.
Mr Andrews has not revealed when lockdown will lift, but said an update on restrictions would occur tomorrow.
"We have made great progress, we have avoided thousands of cases," he said.
"Knowing what we know now lockdown was the right course, the right call at the right time.
"We will not be ready to lift this lockdown at midnight tomorrow night."
13 cases of COVID-19 were recorded in the 24 hours to midnight - of one which was announced on Sunday.
All the new cases are linked to the current outbreak, only one case was isolating during their infectious period.
There are 15,800 close contacts in isolation.
Mr Andrews said there were exposure sites across the state which was challenging.
"There are more than 250 exposure sites that are connected to this outbreak, stretching from Phillip Island to the Mallee," Mr Andrews said.
"This is from one end of the state to the other, not just in Melbourne, but indeed right across the state.
"That is very challenging."
IN OTHER NEWS:
Victoria's snap five-day lockdown was due to end at midnight tomorrow.
It comes as NSW recorded 98 cases of COVID-19 in the 24 hours to 8pm yesterday, 20 of which were infectious in the community.
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