VICTORIA has recorded Australia's deadliest day of the coronavirus pandemic with 19 deaths, as the state reported its lowest number of new cases in almost two weeks.

Australia's death toll has now surpassed 300, with 313 people losing their lives to COVID-19. Of those, 228 were from Victoria.

Authorities had previously warned the state's death toll would rise given the increasing number of COVID-19 infections.

Mildura remains on six total cases, with one active case linked to the region. That case is understood to be an Irymple woman who tested positive in Melbourne and remains in the city in isolation.

There are 7869 active cases in Victoria, of which 1756 are linked to aged care residents and staff.

By contrast, the rest of Australia has less than 300 active cases combined.

Some 640 Victorians are in hospital with the virus, with 47 in intensive care and 31 of them on ventilators.

Victoria recorded 322 new COVID-19 cases on Monday - it's lowest daily figure since July 29, when it recorded 295 new cases.

But Premier Daniel Andrews urged people not to become complacent about the numbers.

"It is really important that we all stay the course on this," Mr Andrews said.

"(COVID-19) is a wicked enemy, it will do everything it can to wear you down and that is where it absolutely flourishes."

Metropolitan Melbourne has been under tough stage-four restrictions - including an 8pm curfew - for a week, while regional Victoria is under stage-three measures.

The lockdowns are in place until September 13.