Victoria recorded no new cases and no further deaths on Monday for the first time since early June.

The number of mystery cases has dropped to seven and Melbourne's 14-day average is down to 3.6.

Acting Chief Medical Officer Paul Kelly says it's another story behind the numbers, in relation to the state's complex outbreak in northern parts of Melbourne.

But Professor Kelly said the state's contact tracing ability had rapidly improved.

"These are good signs, and we will of course only really know how good they are once some of the social distancing and other lockdown measures that are happening in Melbourne at the moment are released," he told a Senate estimates hearing.

Victoria's positive figures have increased expectations Daniel Andrews will announce the lifting of more restrictions.

The premier was widely expected to outline the easing of restrictions over the weekend, letting down many when he decided to wait.

The prime minister said it was profoundly disappointing Mr Andrews had delayed the loosening of lockdown rules.

Scott Morrison issued a joint statement with his treasurer and health minister, who are both Victorian, highlighting the health and economic impacts.

"At some point, you have to move forward and put your public health systems to work," they said.

"The decision to keep businesses closed suggests that there is still not sufficient confidence within the government that their systems can support reopening."

Mr Andrews insists the state is still on track to reopen before November 1.

But his federal Labor colleague Bill Shorten said he could understand why many Melburnians were disappointed.

Business groups have been scathing of the premier's "inexplicable" delay, describing it as a hammer blow.

"Many businesses probably would have hoped with some indications that we were going to get more restrictions lifted yesterday," Mr Shorten told ABC radio.

"I am quietly confident that a further loosening of these restrictions could be announced in the next couple of days, or even by the end of the day."

Mr Shorten criticised the federal government for bagging the state government rather than recognising the good work of Victorians in suppressing the spread of coronavirus.

Australian Associated Press