The owner and chairman of Super League side Hull Kingston Rovers has warned French club Catalans Dragons they could face legal action as a result of signing Israel Folau, the BBC reported on Tuesday.
The broadcaster said it had obtained an email in which Neil Hudgell put the Dragons "on notice" should Hull suffer financial loss due to the signing of the former Australia rugby union international.
‘CHANGED THEIR MINDS’: Dragons backflip on initial Folau plans
Folau reached a settlement with Rugby Australia in December after his contract was torn up in May for posting a meme on social media that said hell awaits "drunks, homosexuals, adulterers" and other groups.
"I reserve my position to take proceedings v Catalans Dragons," the BBC quoted Hudgell as saying.
In the email, he suggested action could be taken if a title sponsor withdrew, external investment was not secured or "quantifiable reputational damage is caused to the brand of Super League and its members".
The BBC quoted one senior club source as saying "nearly all" the Super League clubs backed Hudgell's position.
There was no immediate response to a request for comment from Hull.
Dragons chairman Bernard Guasch has said they wanted to give Folau a "new opportunity" but the club did not share the player's religious beliefs.
Super League executive chairman Robert Elstone has said Folau's comments go against the sport's core values.
"I have sought the opinion of informed voices connected to our game, and the majority share my disappointment that one of our clubs has chosen to sign him," he said in a recent statement.
"There is a strong feeling that the decision to sign him lets down many people connected to our sport."
Folau breaks silence
Speaking to Sky Sports on Tuesday, and avoiding any reference to the controversy, Folau said he was "super-excited" to be back in the game he grew up playing and looking forward to the challenge.
"It's been 10 years since I last played rugby league and I'm grateful for the opportunity to be part of a great organisation, great team," he said.
"I miss that team camaraderie, the team environment and being around your team mates and being able to train with your team."
Dragons head coach Steve McNamara told Sky TV that the club knew Folau's signing would be controversial but they had needed to fill a position.
"We looked in France and England and overseas, in the southern hemisphere both in rugby league and rugby union. We went down the route of investigating a fair few players and Israel's name was on the list.
"And having spent a lot of time speaking to him and understanding him a lot more, and getting the reassurances that we did, we made a decision as a club that we would support the signing of Israel and give him another opportunity in our game."
Israel Folau has begun training with his new teammates in the south of France and could make his Super League debut as soon as Sunday at Wakefield.