Cruise ships on opposite sides of Australia are locked in standoffs with authorities about their immediate fate.

The German cruise ship Artania – on which scores of people became infected with coronavirus – remains docked at Fremantle, despite being ordered by Australian Border Force to leave.

It has 12 passengers still on board, some of them too unwell or frail to fly home. There are also about 500 crew – who have asked to remain in port for another two weeks.

The two-week timeframe is seen as a way to determine whether anyone still on board the Artania has the virus, and to ensure they can be treated if they do.

The standoff came as Australia’s coronavirus toll rose to 20 on Wednesday, with the death of a 95-year-old woman in a Sydney hospital.

Federal Attorney-General Christian Porter said WA had a humanitarian obligation to ensure the Artania’s frail and ill passengers were fit for their journey home.

Seven people from the ship are in intensive care in Perth hospitals, which are also treating dozens of other patients from the vessel.

Hundreds of Artania passengers flew home to Frankfurt from Perth at the weekend.

“My information is that there are still 12 passengers on board, some of whom are very unwell and their level of either illness of frailty is such that they cannot get in a plane,” Mr Porter told 6PR radio on Wednesday.

“We’ve got a responsibility to those passengers to ensure the West Australian health system gives them the available attention to ensure that they don’t – if I could put this bluntly – die on the voyage home because they’ve not received proper attention.

“We have a humanitarian obligation.”

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However, Premier Mark McGowan wants the ship to leave immediately.

“I’m very disappointed and I’d urge the Australian Border Force and the federal government to take steps to get the ship away,” Mr McGowan said Wednesday.

“We’ve got to get the ship on its way. It has to go back to Germany,” he added.

An ABF spokesman confirmed all foreign-owned cruise ships had been ordered to leave Australian waters. But Mr Porter said the Artania did not need to go immediately.

Fremantle Ports has the Artania scheduled to leave at midday on Friday.

Meanwhile, the operator of the Ruby Princess cruise ship – one of nine cruise ships either docked in NSW or waiting off the coast – has asked the NSW government to take a humanitarian approach to its crew members who are ill with COVID-19.

On Tuesday, NSW Police Commissioner Mick Fuller urged foreign cruise ships lingering in Australian waters to return to their home ports immediately, fearing they might flood Australian hospitals with sick passengers and crew.

There are more than 400 coronavirus cases from Ruby Princess. Photo: AAP

“All the hard work we’ve done could be over. We will continue to allow them to have fuel and food … but it is time to go to your port of origin,” Mr Fuller said.

Carnival Australia, however, said it was not safe for the ship to sail away from Australia with sick crew members on board.

“While illness on board has been reduced due to strong health management, the ship needs to remain within reach of Australia to access healthcare services if an urgent need arises,” the company said on Wednesday.

Six seriously ill crew members have already been transferred from the Ruby Princess to NSW hospitals.

The PM said on 15 March that the federal government would stop the cruise ships. That did not happen.
4 days later the Ruby Princess arrived and disembarked all its passengers – without screening or quarantine. The calamitous results keep piling up. 👇 https://t.co/OTR94fg4H1

— Kristina Keneally (@KKeneally) March 31, 2020

Carnival said it is “in high-level federal and state discussions with the aim of enabling the repatriation on compassionate and humanitarian grounds”.

There are 1100 crew on the Ruby Princess from 51 countries. The ship is registered in Bermuda, but Carnival says its home port is effectively Sydney as it was in Australia on a six-month cruise season.

The Ruby Princess has become a major source of COVID-19 cases in Australia after infected passengers were allowed to disembark without adequate checks.

There are 324 coronavirus infections in NSW linked to cruise ships, including 211 cases from the Ruby Princess and 79 from the Ovation of the Seas.

The Guardian is reporting at least 440 passengers across six states and two territories had tested positive for COVID-19 after disembarking from cruise ships.

-with AAP