Melbourne wharfies have been stood down after refusing to unload a container vessel they fear may carry coronavirus.

The Maritime Union of Australia said the XIN DA LIAN docked at the DP World terminal on Tuesday night “in breach of the federal government’s 14-day coronavirus quarantine period” and wharfies identified it as “a risk to workers and the community”.

“The largest cluster of COVID-19 cases in Australia - which has already claimed several lives and caused hundreds of illnesses - was the result of inadequate measures put in place for the arrival of ships. What’s the difference with this ship?” MUA Assistant National Secretary Warren Smith said in a statement.

He said allowing the container vessel to breach the coronavirus quarantine period was simply too great a risk.

“Wharfies don’t want to see a repeat of that blunder on the waterfront, but we still see ships allowed to dock inside of quarantine periods in breach of Australian Government Department of Health guidelines,” he said.

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Mr Smith said the union had been demanding improvements to biosecurity measures since January.

He said it would continue to fight for strict enforcement of quarantine periods, more proactive biosecurity measures, testing for workers and crew of international vessels arriving in Australian ports and support for sick crew members.