Western Australia has recorded no new cases of COVID-19 overnight, the first day with no new confirmed cases of the virus in more than five weeks.

Key points: The last time WA recorded a day with no new COVID-19 cases was March 12

The last time WA recorded a day with no new COVID-19 cases was March 12 Premier Mark McGowan says all of WA's strict measures have played a role

Premier Mark McGowan says all of WA's strict measures have played a role But he says it is not the time to become complacent about the virus

"We had zero additional cases of COVID-19 in the last 24 hours," WA's Premier Mark McGowan said.

"This is an outstanding result. One we can all be very proud of."

Mr McGowan said the result showed the tough approach taken by the state to contain the virus — including a hard border closure to the rest of the country — had been effective.

WA COVID-19 snapshot Confirmed cases so far: 662

Confirmed cases so far: 662 Recovered: 650

Recovered: 650 Deaths: 9

Deaths: 9 Total tests: 395,402 Latest information from the WA Health Department





"Western Australia's response has been a stand-out," he said.

"The strict measures introduced, the tough border closures and the regional travel restrictions — these have all played a major role in our success in minimising the spread and the impact of COVID-19."

The last time WA recorded a day with no new cases was March 12.

A coronavirus milestone

WA Health Minister Roger Cook said the absence of reported cases overnight represented a milestone in the battle against the virus.

"I know it's tough and I know it can be lonely but we are winning this battle together," Mr Cook said.

Roger Cook says 435 people have recovered from COVID-19 in WA. ( ABC News: Hugh Sando )

"Every Western Australian can be proud of this result, but our work here is not done.

"We must continue to listen to the health advice, to do what is asked of us because it will save lives."

The number of diagnosed cases remains at 545, while the total number of active cases has dropped to 103 with another nine recoveries overnight.

The total number of recovered patients is 435 — 48 of those are from regional parts of the state.

Mr Cook said 27 people were being treated in Perth metropolitan hospitals, six of those patients were in ICU.

Almost 29,000 people have tested negative for COVID-19.

Mr Cook said the Government would need to see low daily case numbers over a sustained period of time before health authorities could advise on the "next important steps".

The Minister said the state would not pursue a New Zealand-style strategy of attempting to eliminate the virus entirely, saying it would continue with the nationally adopted "suppression" approach.

Mr Cook said he would like to see school children included in the State Government's plan for random testing of parts of the community.

No time for complacency: Premier

Mr McGowan warned the state could not let the good work "go to waste".

"We need everyone to say the course," Mr McGowan said.

"I know it's easy to think that we've succeeded and we can just get back to normal, but we need to continue to be very cautious, we cannot get complacent."

Mr McGowan said the situation would be monitored over coming weeks to assess "if and when" some restrictions could be eased.

"But just like our soft and cautious start for schools in term two, any adjustments will be based on the best of health advice and will be considered in detail," he said.

The Premier said one of the biggest threats remained people travelling into the state by air.

"We continue to get a small number of arrivals by air. These are predominantly Western Australians returning home or other Australians travelling onto other cities in the east," he said.

"In the last 24 hours we had a total of 176 people arrive either on domestic or international flights. Of those 72 were exempt and 82 were placed into quarantine for the next 14 days."

Mr McGowan said authorities were working to determine future incoming international arrivals.

"While we have very little evidence of community transmission in WA, our biggest threat continues to be these kind of arrivals from overseas or over east."

The Artania cruise ship left Fremantle at the weekend, after being docked in WA for more than three weeks. ( ABC News: Andrew O'Connor )

Bars, restaurants to stay closed for now

Despite the promising numbers, Mr McGowan ruled out a quick opening of bars and restaurants.

"The immediate future of course is in the eye of the beholder, but I think that's right for the short term," Mr McGowan said.

"The only way forward really is to listen to the medical advice."

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The Premier also flagged more support for renters and landlords to be announced over the coming days.

"Essentially it's support for small-business people and support to either residential renters or landlords, but the final details are being worked out."

The State Government pledged $735,000 to Homeless Healthcare to support its mobile street health program for an additional six months.

Mr Cook said the service would now be able to expand its program to seven days a week, and employ an additional GP and extra community caseworkers.

"We know that the COVID-19 virus preys most upon those vulnerable in our community and this funding represents a good opportunity to continue to make sure that we look after the homeless," he said.

App eases pressure on WA borders

Mr McGowan said 49 foreign nationals remained in WA from the Artania cruise ship that left Fremantle at the weekend.

Ten of them were in hospital and the rest were in hotel quarantine, with authorities working to get those people home safely.

The Premier said the soft launch of an app, G2G, which has been repurposed to help process people at the state's regional and border checkpoints, was already proving popular.

Mr McGowan said people and businesses exempt to travel restrictions could apply for approval through the app to help "streamline the process" of getting across borders.

"It will give people confidence that they are approved to travel into a different region ahead of the journey," Mr McGowan said.

WA Police Commissioner Chris Dawson said it was important to remember the new border checking system was not a tracking app, but a system to make it easier to move around the state.

"This will actually make it far more efficient," he said.

Meanwhile, police have handed seven members and associates of the Outlaws motorcycle gang $1,000 fines after they were spotted congregating outside a hotel on George Street in East Fremantle late last week.

Officers said the men failed to comply with Emergency Management Act social distancing provisions.

Government coffers to take a hit

WA's Treasurer Ben Wyatt has warned state revenue was likely to take a significant hit in the wake of the coronavirus crisis.

Mr Wyatt said he expected "very, very large" write-downs in payroll tax, the GST pool and property-related taxation.

"I am expecting [them] to be written-down, not just in this year but for the next couple of years," he said.

"I suspect the revenue impacts will be perhaps even more considerable than the spending impacts."