The WA Government is planning to restrict travel between Western Australia's regions to halt the spread of COVID-19 as residents have been advised to cancel holidays within the state.

Key points: WA residents are being asked to cancel Easter travel plans

WA residents are being asked to cancel Easter travel plans Two children under 10 are among 35 new cases reported on Tuesday

Two children under 10 are among 35 new cases reported on Tuesday Perth Stadium will be used as a COVID-19 command centre

The number of WA cases of the virus increased again overnight, with 35 new infections recorded, including two children aged four and 10.

The travel announcement came as massive queues formed on the WA/SA border, as travellers rushed to get back into the state before Tuesday's 1:30pm deadline.

"Our new border restrictions have helped put a complete stop, a major stop, or major restriction, on any unnecessary travel interstate," Mr McGowan said.

Long queues have formed at the WA/SA border crossing as desperate travellers try to return home. ( ABC News: Rhiannon Stevens )

"I also want to expand that advice across Western Australia.

"That means that any unnecessary intrastate, internal travel in Western Australia needs to be avoided."

Mr McGowan made the announcement after plans emerged for WA to expand its coronavirus testing criteria and as the state official shut its borders from 1:30pm on Tuesday.

Two young children diagnosed in WA

There have now been 175 confirmed cases of COVID-19 diagnosed in Western Australia.

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





The ages of the new cases range from four to 76, and include two young children both from the same family who contracted the virus from a known contact.

Five of the new cases are located in regional WA.

Two people have contracted the virus in the Kimberley region, one in the Mid West, one in the Wheatbelt and one in the Great Southern.

"Of these new cases, eight are passengers of the Ruby Princess and four are from the Ovation Of The Seas — the cruise ships that were docked in Sydney Harbour," WA Health Minister Roger Cook said.

"Now you see just what an impact those two cruise ships have had nationally."

Regional lockdown would spell devastation for businesses

Mr McGowan conceded the travel restrictions on the state's nine regions would be met with complaints, acknowledging the measures were "extreme".

He said it was likely the Perth and Peel areas — which stretches south from Perth down to the city of Mandurah — would be considered one region under the restrictions.

WA Premier Mark McGowan has thanked West Australians for their understanding, describing this as a "very, very difficult time". ( ABC News: Hugh Sando )

The Premier said a full state lockdown was "constantly under consideration".

"That will be no doubt a discussion over the coming days and weeks but just understand the consequence of that — we're going to make millions of people unemployed," Mr McGowan said.

"Public health is incredibly important but you've also always got to balance that we need to provide essential services.

"That will be devastation for hundred of thousands of businesses and you don't make that decision lightly."



Essential travel to still be allowed

Mr McGowan said the stricter travel restrictions within the state would help to stop the spread of the virus and better protect some of WA's most vulnerable residents.

"We'll be putting in place restrictions on the movement between Western Australia's regions," Mr McGowan said.

"Clear guidelines around this will be released soon.

"Essential travel cannot be avoided. That is understandable. But we need to avoid everything else.

"I'm asking West Australians for their understanding during this very, very difficult time. This measure we're putting in place in the future will protect our regional citizens, especially the elderly and especially Aboriginal people."

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WA Police Commissioner Chris Dawson said if people were planning on travelling down south from Perth, for example, they should cancel those plans.

Commissioner Dawson said if the community does not follow the advice, including self-isolating and not panic buying, stricter rules across the board will be put in place. ( ABC News: Hugh Sando )

"If you're in Perth and you are planning to spend Easter in the South West, you need to change your plans," the Commissioner said.

"I would strongly suggest that you probably won't find too much to do down there and in fact you may be stopped from going there.

"This is where people have to think through this carefully and not think about it [as] a normal situation.

"This is abnormal. It is extraordinary, it is a state of emergency."

Beaches could be closed

The Premier delivered a strong warning that Perth's popular beaches could also be closed soon if people ignored social distancing measures.

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





"If we see people not doing the right thing at our beaches, like Cottesloe or Scarborough, we will need to act," Mr McGowan said.

"That means, we may be forced to close down these or other beaches.

"I don't want to be doing this, but if we have to protect people from themselves on our beaches then we will."

WA border crossings triple ahead of shutdown

Mr McGowan said WA's border restrictions, which came into force at 1:30pm on Tuesday, had resulted in three times the usual number of people trying to cross the South Australian border into the state.

Cars line up at the border of Western Australia and South Australia as border restrictions come into effect. ( ABC News: Jarrod Lucas )

"Six hundred and seventy five vehicles crossed at Eucla and 150 at the Northern Territory border," Mr McGowan said.

"There are long queues at the South Australian border today. This is unprecedented and it's never happened before.

"However, as there are major delays, we ask people to be patient.

"I want to make sure people who are at the border right now know if you reach the border by 1:30pm — that includes waiting in the car in the queue — we'll make sure you come into WA without restrictions in force."

Mr McGowan said after that though, it was too late for tourists.

"If you are a tourist and want to come to WA, it's too late. Please don't come," Mr McGowan warned.

Perth stadium becomes emergency command HQ

Perth Stadium has been transformed as one of four West Australian coronavirus crisis "incident command" centres in a coordinated state effort to tackle the virus outbreak.

"This is one of four centres in which we are both coordinating and commanding a state of emergency," Police Commissioner Chris Dawson said.

"The centre has been established here at [Perth] Stadium to ensure police are maintaining law and order and providing support to mitigate the impact of COVID-19 on our community.

WA Police are using Perth Stadium as a coronavirus base amid the growing outbreak. ( ABC News: Rebecca Carmody )

"Police will track workforce impacts and planning for the need for essential services across Western Australia.

"They will turn the directions that come out of the State Emergency Committee meetings, which happened at least twice a week, into operational guidance for officers to ensure the resilience and continuity of law and order in Western Australia."