Australia has barred 11 cruiseships from docking and 11,000 crew members from repatriating over coronavirus fears, but the nation's seafarers union is urging their welcome to prevent a humanitarian crisis.

Home affairs minister Peter Dutton has alleged that some are giving false numbers after the release of new data from vessels off the nation's coast, The Financial Times reported.

“It’s clear that some of the companies have been lying about the situation of the health of passengers and crew on board,” Dutton told publication.

Australia would bring doctors aboard to determine the level of risk posed by possible coronavirus infections, he said.

The Maritime Union of Australia (MUA) is pushing back against its government, telling authorities that the crew members must be allowed back on land as soon as possible.

“The plight of the thousands of crew members on board foreign cruise ships anchored in Australian waters is an emerging humanitarian crisis that requires immediate government action,” said Paddy Crumlin, MUA national secretary and the current president of the International Transport Workers’ Federation.

“The Australian Government must urgently act to allow the safe repatriation of all crew members not essential for marine operation to their home countries."

The crews aboard these ships, owned by Carnival Corp and Royal Caribbean Cruises, must be tested for Covid-19 after the vessels are completely disinfected, the union said. The owners must also make sure that the seafarers are returned home at company expense.

Australian taxpayers shouldn't pay for this

“Not a single cent should be paid by Australian taxpayers to support or bail out these international companies that have spent years using flags of convenience and opaque ownership structures to avoid paying local taxes and exploit workers," the union said in a statement.

Almost 500 Covid-19 cases in New South Wales were traced back to four cruise ships owned by Carnival and Royal Caribbean.

Carnival's Ruby Princess had been linked to 340 cases in the state.

Royal Caribbean is "in continuous contact with government and public health authorities" and appreciate their help in protecting the health of its crewmembers, spokesman Jonothan Fishman said.

"The well-being of our crew is our foremost concern, and we are communicating with them directly as we continue to implement rigorous health protocols, provide medical resources and support, and follow enhanced cleaning and sanitization procedures onboard our ships," he told TradeWinds.

Calls to Carnival were not immediately returned.