Clive Palmer has threatened to take Queensland Rugby League to Federal Court if they don't approve Israel Folau's registration by Wednesday.
Minerology, the company owned by Palmer, is bankrolling Folau's bid to play rugby league for the Southport Tigers in Gold Coast's A-Grade competition this year.
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The 32-year-old dual international is hoping to play alongside brothers John and Eni in the third-tier competition.
Palmer, a billionaire mining magnate, has indicated he wants Folau to be on the field for Southport's clash against Burleigh Bears at Pizzey Park this Saturday.
The QRL has previously indicated it would consider Folau's application to be registered "in line with its rules and processes".
However Palmer says he'll take legal action if the decision isn't made by the middle of this week.
"Israel doesn't drink, smoke or take drugs. He has never been charged with a criminal offence" Palmer said in a statement released late on Sunday.
"He loves his wife and his son. He has a rugby playing record second to none.
"If he is not registered by Wednesday, I believe he will issue an injunction in the Federal Court of Australia against the QRL for their discrimination against him on religious grounds."
Israel Folau's bid to return to rugby league
Folau last played rugby league in Australia in 2010 before pursuing a short-lived AFL career with expansion club GWS and then a rugby union career which included 73 Test appearances for Australia.
He had his contract terminated by Rugby Australia in 2019 after saying "hell awaits" gay people in a social media post.
The 32-year-old then returned to professional rugby league after reaching a legal settlement with RA following his sacking, joining Super League club Catalans in January of 2020.
The France-based club have indicated they are considering legal action of their own in the wake of Folau's Southport announcement.
Catalans' football manager Alex Chan said they expected Folau to return at some stage during the year having granted him compassionate leave to deal with family matters in Australia.
Palmer has previously dismissed any suggestion Catalans have a case for compensation.
"The truth about it, and we've had a look at that, obviously before we signed Israel up, is he signed a contract with them in January," said Palmer.
"It required them to make substantial payments to Israel, which they've failed and defaulted in doing. So in a legal sense they've repudiated that contract.
"Israel's accepted that repudiation and the contract's terminated. That's the legal position, so they don't have a leg to stand on."
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