An Australian couple suffering from a deteriorating COVID-19 condition were evacuated from a cruise ship stranded off the coast of Uruguay and taken to hospital, the Uruguayan navy said on Wednesday.

Eight people out of the more than 200 aboard -- 128 of whom have tested positive for the new coronavirus -- have now been transferred to hospitals in Uruguay's capital Montevideo.

The navy posted a picture on Twitter of the raft that took the tourists, "aged 59 and 60, both with pneumonia and coronavirus," ashore.

Foreign Minister Ernesto Talvi had said on Tuesday night that two more people aboard the Australian-owned Greg Mortimer would need to be brought ashore.

"Their health is deteriorating and they're going to need to be taken to hospital in Montevideo," Talvi said.

The liner, owned by Aurore Expeditions, has been anchored 20 kilometers (12 miles) off the port of Montevideo in the Rio de la Plata since March 27.

Uruguay, which is assuming that everyone aboard has contracted the virus due to the lack of isolation measures deployed on the liner when the first cases emerged, has said only those whose "life is at risk" will be allowed off the ship.

The six people previously taken off the ship -- three Australians, one Briton and two Filipino crew -- are in a stable condition in hospital, Health Minister Daniel Salinas told AFP on Tuesday.

Uruguay has authorized a humanitarian flight to evacuate Australian and New Zealand passengers to Melbourne via a "reinforced sanitary corridor" following "intense conversations and very close cooperation with the Australian government," Talvi said.

Eight people have been evacuated from the Greg Mortimer liner due to showing serious signs of the COVID-19 disease
Eight people have been evacuated from the Greg Mortimer liner due to showing serious signs of the COVID-19 disease AFP / Pablo PORCIUNCULA

Australian Foreign Minister Marise Payne confirmed on Wednesday that authorities were working together to try to repatriate as many Australians as possible.

"The Greg Mortimer is a very difficult situation," said Payne.

"So we are working very closely to try to finalise this charter flight as soon as possible and to ensure that the maximum number of Australians who are on that vessel are able to fly."

That includes both those to have tested positive and negative. Once arriving in Melbourne they will all be required to stay in isolation for two weeks.

The Airbus A340 plane contracted to fly the Aussies and Kiwis home "is configured with medical facilities aboard... to look after the health and security of everyone," said Aurore.

However, there are no plans yet to repatriate European and American passengers.

They must "wait until they test negative" before organizing their repatriation via Sao Paulo, Brazil, the ship's owner said.

Those to have tested negative could be evacuated in the coming days "subject to a second test and permission from the Uruguayan government," Aurore said.

The cruise ship was originally due to tour Antarctica, South Georgia and Elephant Island but the expedition was called off on March 21 after South American countries and Australia started closing their borders and imposing strict lockdown regulations.

With ports all along the Atlantic coast of South America closed, the Greg Mortimer was forced to sail to Montevideo, more than 2,600 kilometers from South Georgia.