Australian Prime Minister Scott Morrison has issued his toughest criticism of the Victorian lockdown to date urging the state to re-open the economy faster by improving Covid-19 contact tracing just as NSW has done across the border.

Warning he will adopt a "wait and see" approach to further cash assistance for the state, the Prime Minister has put the Victorian Premier on notice that he must step up to bear more of the financial burden for the decisions he is making to keep the economy in the deep freeze.

"Lockdowns and borders are not signs of success in dealing with Covid-19. And so it's important that we put ourselves in a position where they do not feature in how Australia is dealing with Covid-19 on a sustainable basis," the Prime Minister said.

"The most important thing is ensuring that we build an integrated tracing capability right across the country.

"As I've noted, New South Wales is the gold standard. That is where we have to get everybody to ensure that Australia can be open."

Morrison said the Commonwealth could not step in and take control because it was a matter for the states but he urged Andrews to consider a faster timetable.

"I see it as a starting point in terms of how this issue will be managed in the weeks and months ahead in Victoria," he said.

Morrison said officials would be "interrogating" Victoria's modelling and providing "constructive feedback" on the exit plan.

"Australia can be open. And the plan that we will work on with the states and territories is to get ourselves to that standard so Australia can be open.

"We will continue to carefully review this plan. We're yet still to receive the detailed modelling."

The Prime Minister repeated his claim – disputed by the Victorian Premier – that NSW would be under lockdown.

"What I can't help but be struck by is that, under the thresholds that have been set in that plan, Sydney would be under curfew now. Sydney doesn't need to be under curfew now. They have a tracing capability that can deal with outbreaks."

The Prime Minister warned while he would consider extra assistance, he wanted Victoria to outline what assistance it was offering to workers to businesses before tipping more money into the state.

"Victorians are being supported more by the federal government than any other state and territory,'' he said.

"I'll be looking to see what they'll be doing first before the Commonwealth considers any responses that we'll be making."

Victorian Premier Daniel Andrews said yesterday Melbourne will not move into the next stage of restrictions before September 28, even if it meets the daily case threshold earlier.

But it may move into later stages of the state's road map to recovery sooner than expected including ending the nightly curfew, allowing restaurants to re-open outdoors, stay at home orders that are tentatively planned for October 28, based on daily case numbers.

Cafes and restaurants will be banned from serving patrons indoors until late November under the current road map.

During the press conference, Health Department chief Brendan Murphy said some of the triggers for removing restrictions in Victoria were very "conservative".

"There's no rule book for this virus but I think some of us feel that, if there were more confidence in the public health response capability, you could take some slightly more generous triggers."

Health Minister Greg Hunt joined the criticism of his home state of Victoria, reading from a pre-prepared list of experts who had criticised Victoria's contact tracing.

"Professor Tony Blakely, from the University of Melbourne, an author of the modelling, subsequently said, 'If we do our contact tracing better than we did three months ago, the contact tracers may be able to hold the case count without it going up again as badly as our model suggests'.

"Professor Peter Colignon from the Australian National University in Canberra: 'A lot hinges on contact tracing. So far, Victoria has not been able to do that as well as other states. I think actually a more nuanced approach like New South Wales is doing where very good contact tracing is likely to be sustainable over the long-term'."

The Prime Minister did not rule out more assistance for Victoria but stressed the ball was in the Victorian Premier's court given that it was his decisions that had kept the economy in the deep freeze.

"We are extending the JobKeeper payment. We are extending that out till the end of March. We are extending the JobSeeker payment out to the end of December," Morrison said.

"There are a million Victorians who've been supported by those payments up until now, and they will continue to be."

The Prime Minister made the comments at a press conference yesterday on the latest deals the Commonwealth has signed to advance planning for a Covid-19 vaccine.