Victoria records 177 new coronavirus cases as NSW pub outbreak expands to 21

Meanwhile, the NSW chief medical officer said the sate was at 'a critical time' in getting on top of the outbreak sparked at a south-western Sydney hotel.

The number of confirmed cases connected to the Crossroads Hotel in Casula has ballooned to 21, 10 patrons and 11 close contacts.

Anyone that had visited the venue between July 3 and 10 must now isolate for 14 days and were being urged to get tested.

There were 21 new cases reported in NSW on Monday, chief medical officer Kerry Chant announced.

"This is a critical time, where I urge you to come forward for testing," Dr Chant said.

"Now was not the time to be going to workplaces, pubs, clubs, or anywhere if you have any symptoms.

"If you are out and about and you can't socially distance, then wearing a mask is an additional measure you could put in place. But it shouldn't be at the expense of social distancing, and we wouldn't want people to fall into a false sense of security."

She said the fact all cases were connected either to the Crossroads Hotel or a known case was a success as authorities were then able to stop those people spreading it further.

"If we see any emergence of cases that are not linked to either known cases or Crossroads attendance on those days, then obviously that will lead us to reflect on additional measures," she said.

One person connected to the Crossroads Hotel outbreak also visited the Picton Hotel, using the gaming room on July 4, 9 and 10, which saw the hotel closed on Monday for cleaning.

Sydney's Star Casino also confirmed a patron tested positive after visiting the casino on July 4. However, the casino claimed it was cleaned thoroughly daily and remained open.

There are several facilities across NSW which have reported a visit from a person who has since tested positive for coronavirus. These venues are:

Anyone who has visited these venues recently and develop even mild symptoms should isolate and get tested.

Major General Paul Kenny confirmed 12 defence force members from the Wagga RAAF base who attended the Crossroads Hotel had tested negative for coronavirus but would still complete the 14-day isolation period.

Federal health minister Greg Hunt announced on Monday afternoon a further 1000 defence force personnel would be deployed to Victoria in response to the outbreak.

He also announced 5 million masks from the national stockpile would be distributed in Melbourne after health officials said anyone in Melbourne or the Mitchell Shire should wear a mask.

"The Australian government is providing additional support, both on the containment front, and on the capacity front, for Victoria's healthcare system, in partnership with the Victorian government," Mr Hunt said.

Mr Hunt said the ADF would assist Victorian authorities with monitoring isolation, testing, checkpoint control and other roles where the Victorian government requests assistance. The 1000 personnel is in addition to 350 ADF personnel currently working in Victoria.

Of the 5 million masks to be distributed, 1 million will go to frontline health staff and 4 million into the aged care sector.

"These are very important distributions to allow for greater use of [personal protective equipment] to make sure that all of the needs are met," Mr Hunt said.

"We are getting ahead of the curve, and this will be fundamental. We know that our aged care homes are an area of risk."

It was also reported on Monday afternoon that a second person from Victoria that had travelled in the Merimbula area tested positive to coronavirus.

This person visited the Merimbula RSL on July 6 and the Waterfront Cafe in Merimbula on July 7.

While investigations were ongoing NSW Health advised anyone that had attended these areas to monitor their health and get tested immediately at the onset of any symptoms.

Victorian Premier Daniel Andrews announced of the 177 new cases 25 were connected to known cases and 151 others were under investigation.

There are 1612 active cases across Victoria, 72 people were in hospital with 17 in intensive care.

Mr Andrews repeated his plea to Victorians to continue abiding by lockdown restrictions and for people to follow guidelines on social distancing and hygiene.

"Our nurses, doctors, ambos, all those clinical staff, we shouldn't see them as the front-line in our war against the battle, they're the last line of defence," he said.

"We should be grateful in every sense for the work they do, but we've got to see ourselves, each of us, as the real front-line in our fight against this virus.

"If we all keep following those rules, then this strategy will work, we'll bring it under control, we'll be able to resume opening up, we'll get past this very difficult set of circumstances we face.

"To the vast majority of people doing the right thing, I say thank you, thank you so very much."

Mr Andrews reiterated the lockdown in Victoria would continue for as long as it was deemed necessary and chief medical officer Brett Sutton said it was possible Victoria had yet to meet its case number peak.

"I'm not going to be complacent about today's number," Professor Sutton said.

"It's great it's lower than our peak. But it may not be our peak yet.

"So I would like to see a week of decreasing numbers before I come and say I have greater confidence about the direction we're going in."