WA Premier Mark McGowan is "exercising the Rottnest option now" to quarantine Australian cruise ship passengers set to disembark in Perth, as two other vessels have been prevented from docking.

Key points: Rottnest will be used to quarantine 800 Australian passengers for 14 days

Rottnest will be used to quarantine 800 Australian passengers for 14 days Two cruise ships are being kept offshore with one reporting illness

Two cruise ships are being kept offshore with one reporting illness WA has recorded 30 new cases of coronavirus, bringing its total to 205

Australians on board the Vasco da Gama cruise ship due to arrive at Fremantle Port on Friday will be taken to the holiday island off Perth's coast and required to self-isolate for two weeks.

"All Australians, including the West Australians, will be immediately transferred to Rottnest Island for 14 days of self-isolation," he said.

"In the last two days we have cleared the island of visitors and made arrangements for accommodation, catering and security.

"We are exercising the Rottnest option now."

The Vasco da Gama is carrying 950 passengers and 550 crew and there are 800 Australians on board, including 200 West Australians.

Three Rottnest ferry companies will be used to transport the Australian passengers to the island in small groups.

Mr McGowan said two other cruise ships, the Artania and the Magnifica, were being prevented from docking at Fremantle Port and had been told to anchor offshore, with illness reported on board the Artania.

The Artania is anchored off Fremantle and has requested help to test for coronavirus. ( ABC News: Rob Koenig-Luck )

"Those two ships need to go home, they need to leave and go home," he said.

Internationals to be kept on board Vasco da Gama

The Government said it believed there were 109 New Zealanders on board the Vasco da Gama and the remaining passengers were from other countries, including 33 from the United Kingdom.

The Vasco da Gama is due to arrive at Fremantle Port on Friday. ( ABC News: Tom Fedorowytsch )

"We are currently determining with the Commonwealth if some of the international passengers are in fact permanent residents of Australia," Mr McGowan said.

"Fremantle is the final port of call for this cruise ship as it has always been the plan for passengers to disembark in Fremantle.

"All crew and foreign nationals will remain on the ship until arrangements are made to fly them directly out of the country.

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"They will not be allowed to disembark at any time unless it is to travel under strict supervision directly to the airport, or they need urgent medical attention to survive.

"Passengers who need to travel home to New Zealand will also remain on the ship and a plan is being worked up with the New Zealand Government to get those passengers back home as safely as possible."

Cruise ship says it received no warning

Vasco de Gama operator Cruise and Maritime Voyages (CMV) said it received no warning of the WA Government's decision.

"We would like to express our disappointment that the WA Premier did not inform us of this decision before sharing this news with the public, and that we were unable to inform our passengers before it appeared in media reports," CMV Australia managing director Dean Brazier said.

The Vasco da Gama is due to arrive at Fremantle Port on Friday. ( ABC News )

Mr Brazier said there were no reported health issues on board the cruise ship and passengers would have been at sea for almost two weeks straight when they arrived in Fremantle.

"Our guests will have been at sea for 13 days straight without disembarking the ship or being in contact with anyone who was not a guest or crew member of CMV," he said.

"We are disappointed that they will now have to wait a further 14 days until they can return home."

Phuket in Thailand was the last place the Vasco da Garna visited before starting its journey back to its home port of Fremantle.

Artania cruise ship reports illness offshore

WA authorities are providing assistance to the Artania after it approached Fremantle to refuel but was told to anchor off the coast.

Mr McGowan said about 25 passengers and crew on board the vessel were reporting respiratory symptoms.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 16 seconds 1 m 16 s WA Premier says two cruise ships are being prevented from docking in Fremantle

The Premier said one passenger who was no longer on the ship had tested positive to COVID-19 after disembarking.

"Last night the ship requested assistance with health assessments and COVID-19 testing," Mr McGowan said.

"Health Department officials are now on board providing medical checks and testing. We will receive that advice later today."

There are more than 800 passengers and 500 crew on board but none of the passengers are Australian.

Magnifica returns to Fremantle

The Magnifica left Fremantle yesterday carrying mainly European tourists after making a brief refuelling stop en route to Dubai.

But overnight the Dubai Government told the ship it would not be allowed to dock in the country, forcing it to turn back to WA.

The Magnifica cruise ship is now anchored off WA after being turned away from Dubai. ( ABC News: Fiona Blackwood )

"We continue to deal with the fast moving and internationally complex issue around cruise ship arrivals in Fremantle," Mr McGowan said.

"I will not allow what has happened in Sydney to happen here in Western Australia … It was a complete and utter disaster.

"There are no circumstances where we will allow passengers or crew to wander the streets in our state."

He said the Federal Government had been asked for "immediate assistance" regarding both the Artemia and the Magnifica.

WA coronavirus total tops 200

A further 30 confirmed cases of COVID-19 have been recorded in WA, taking the state's total tally to 205.

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 latest victims are aged between 21 and 80, and eight are from regional WA, with four in the South West, one in the Kimberley, one in the Wheatbelt, one in the Great Southern and one in the Pilbara.

Mr McGowan said about one in four confirmed cases in WA had been linked to cruise ships.

"What is so concerning is that an increasing number of confirmed cases in Western Australia can be traced back to cruise ships," he said.

"I am not going to take any chances on this issue. My number one priority is protecting our citizens here in our state."

Health Minister Roger Cook said five of the latest 30 cases were passengers from cruise ships.

"This takes the total number of COVID-19 positives who [were] passengers on a cruise ship to 47," Mr Cook said.

Mr Cook said two children who were confirmed to have the virus yesterday were both well and self-isolating at home with their families.

McGowan wary of 'Ruby Princess disaster'

Mr McGowan said the Government was exercising the Rottnest quarantine option for two reasons after clearing the island of tourists.

"It sounds extreme and to a degree ridiculous to do it, but I am pleased now we've done it because we now need it," he said.

"One, to protect the safety of the Australian passengers. And two, to protect the West Australian community from any possible infection, transmission from [the Vasco da Gama].

WA Tourism Minister Paul Papalia said around 700 individual rooms were available on Rottnest Island for quarantine purposes.

Mr McGowan said he wanted to avoid the "blame game" currently playing out in New South Wales in relation to two cruise ships that had docked at Sydney Harbour — the Ruby Princess and the Ovation of the Seas.

"I am not interested in playing those games," Mr McGowan said.

"I want to cooperate with the Commonwealth and sort these issues now to avoid the Ruby Princess disaster happening here in our state."