There was a drop in COVID-19 cases in NSW, Victoria and the ACT but people were warned not break the rules with large gatherings to watch the NRL grand final.

A clear message has been issued by health ministers in lockdown - don't use this holiday weekend and the NRL grand final to have large parties.

NSW Health Minister Brad Hazzard warned people on Sunday to be careful and respect restrictions while enjoying the match being played in Queensland to prevent super-spreader events.

"You shouldn't be having people at home," he told reporters in Sydney.

"Your home remains one of the most dangerous places to be in terms of transmission of the virus."

ACT Health Minister Rachel Stephen-Smith offered similar sentiments at her daily COVID-19 update.

"Clearly some people will break the rules, that's really disappointing, and we will encourage people to think twice, three times before they decided they are going to have a grand final party," she told reporters in Canberra.

Both NSW and the ACT celebrate Labour Day on Monday.

NSW reported 667 new locally acquired cases and another 10 deaths, taking the toll in the current outbreak to 372.

It was the first time its daily case numbers have been below 700 since August 19.

Mr Hazzard said the resignation of Gladys Berejiklian did not change NSW's path out of of lockdown.

"The road map has been very carefully worked on by the entire public health team and it will definitely stay the same, unless of course circumstances change in terms of the numbers of the cases," he said.

"It will change only in the sense some medical issue that requires that it needs to be revisited."

Meanwhile, Victoria reported 1220 new cases and three deaths.

Melbourne is preparing to claim the unwanted title of the world's most locked-down city after spending 245 days under stay-at-home orders.

It will surpass the record - set by Buenos Aires, Argentina - on Monday.

Premier Daniel Andrews said he was proud of the sacrifices Melburnians had made over the pandemic and called for them to make one final push over the next few weeks.

"We are going to get past this," he told reporters in Melbourne.

"We are going to end this lockdown and open up and all that we will enjoy then will be a result of all that we have given."

The ACT recorded 38 new cases, a small reduction from the record levels of 52 seen on each of the past two days.

Ms Stephen-Smith was encouraged by the reduction but said it was still above the daily number seen for the majority of days during this outbreak.

The territory is likely to breach the 1000-mark for cases in this outbreak on Monday.

"I suspect what we have seen is a step up in our plateau," the minister said.

"What we have seen it is very difficult to talk about trends on even two or three days data, even a week's data, because we are such a small population in size."

Thirteen new COVID-19 cases were detected in Western Australia, including a dozen crew members from a ship docked at Fremantle.

Four are in hospital in Perth, including two in ICU, according to WA Health.

And a returned traveller in his 30s was taken to a quarantine facility with his family on Saturday after testing positive while self-quarantining in a serviced apartment in inner Perth.