The federal and Western Australian governments are trying to find a quarantine facility to house thousands of sheep and cattle stranded in heatwave conditions aboard a ship that's been at sea for almost a month.
About 16,500 animals are packed into the MV Bahijah livestock carrier, which is understood to be anchored in waters off the coast near Perth awaiting a decision.
The ship was reportedly ordered by the Federal government to turn back from its journey to the Middle East 25 days ago due to security concerns in the region.
Since then, it's been on a voyage to nowhere and arrived back in Australian waters in recent days.
Premier Roger Cook said the ship was likely to dock at Fremantle in the next day depending on traffic in the port.
"The information I have is that the animals are in good condition and good health but obviously everyday they stay on that ship will compromise that situation," he told reporters on Tuesday.
"We're in the hands of the Commonwealth in relation to this but stand ready to support (it)."
Mr Cook said the WA Department of Agriculture was working with the federal government on a plan to unload some of the animals into a quarantine facility.
This included identifying and "standing up" an appropriate facility with biosecurity measures capable of handling the volume of animals.
"It's a difficult situation but it's ultimately the Commonwealth's jurisdiction," he said.
RSPCA WA said action needs to be taken to protect the animals' health and welfare.
Chief executive Ben Cave said sending them back to sea would be cruel and barbaric.
“Heatwave conditions are forecast for the rest of the week," he said on Tuesday.
"These animals have already spent nearly a month on rolling seas in cramped conditions, standing in their own waste and there really is no other humane choice but to get them off the ship now."
Mr Cave also called for independent vets to be allowed to inspect the livestock, which are understood to have been initially loaded onto the ship in Australia.
Perth's temperature is forecast to peak and 38C on Wednesday and 39C on Thursday.