Oleksandr Usyk's promoter says the Ukrainian's undisputed heavyweight title fight with Tyson Fury is in jeopardy due to Fury's financial demands.
The pair have been locked in negotiations for a unification bout but time is running out to agree a deal.
Fury's latest social media announcement appears to have left the fight in serious doubt after he suggested that Usyk should only receive 30 per cent of the fight purse.
"I see all this talk of boxing fights. They want 50 per cent, Usyk and all this, Tyson is being greedy," said Fury.
"Where I'm standing, Usyk, you and your team are worth 30 per cent. You either take it, or you leave it, and if you don't want it, I'll fight Daniel Dubois at The Copperbox and get a few million dollars.
"You want to make some real money, come and fight 'The Gypsy King'.
"But I will say, for every day from today that you linger and mess around, I'm going to deduct one per cent from the 30 per cent.
"Every day, I'm going to deduct one per cent until you take it, and if you don't take it, I'll fight Dubois for $2m. No problem.
"But how in the world did you ever offer me a deal? Not possible. Tick tock, tick tock."
Alex Krassyuk, who represents Usyk, claimed Fury rejected their latest offer where the winner would receive 60 per cent of the purse, and questioned whether the WBC champion actually wants the fight.
- Usyk on Fury: Both of us need this fight
- Shalom: Outside of Fury, Bakole would be Uysk's toughest fight
Krassyuk told iD Boxing: "I can only tell you from the words I hear from my negotiators, my partners Frank and George Warren. According to their reports, Tyson Fury was asking for too much money.
"Even if Usyk would get zero for the fight, it would still not be sufficient for Tyson to cover his [demands].
"Normally when a fighter doesn't want to fight, he asks for something impossible, and then it's not happening. That's according to my experience. I've been in boxing for almost 20 years and that's what I've seen so many times.
"When you're looking for an opponent for your fighter and finding a proper option, and he doesn't want to come, he says, 'pay me 100 instead of five'."
Tyson Fury and his promoters have been contacted for comment.
Usyk on Tuesday said a fight with Fury was "very important for both of us" and that it must be made. The Ukrainian holds the WBA, WBO and IBF heavyweight titles after successive victories over Anthony Joshua.
"All four belts haven't been held by one person," Usyk said, pointing out it has been two decades since the heavyweight division had an undisputed champion.
"So both of us need this fight."
Usyk expects Fury to be even more of a challenge than Joshua but remains undaunted. Previously an undisputed champion at cruiserweight, the 36-year-old believes he can repeat the feat at heavyweight, even against Fury.
"I'm not afraid of Tyson Fury," he said. "This will be like any other fight. It's just a big man who has never lost before against a man who has the WBC belt.
"Of course it's possible to get carried away but actually this is a normal fight for the right to win all the belts.
"If a person is bigger than me, it doesn't mean they're stronger than me. If they have longer arms, it doesn't mean that it will be an advantage.
"I've been boxing since I was 15 years old. They kept telling me that I shouldn't be boxing. They told me that I wouldn't become an Olympic champion or a world champion and that I shouldn't have switched to the heavyweight division.
"But these were opinions from people who couldn't do it themselves. Personally I keep praying and move forward. I don't worry about whether I will reach my destination.
"It's like a samurai. He doesn't have an aim, he has his path. I have my path too."
Shalom: Outside of Fury, Bakole would be Uysk's toughest fight
The world is waiting to see if the undisputed heavyweight title fight between Fury and Usyk can be finalised.
It means the leading contenders in the division are also waiting to see where their opportunities might arise.
French heavyweight, Olympic gold medallist Tony Yoka looks to recover his position when he fights former world title challenger Carlos Takam on Saturday, live on Sky Sports.
After beating Yoka last year Martin Bakole is highly ranked at world level. But promoter Ben Shalom believes that he will need to push for a final eliminator to get a title shot.
"He is in a position where he feels no one wants to fight him and he's going to have to rely on being mandatory," Shalom told Sky Sports.
Bakole has sparred Usyk intensively and so has tested himself against the unified WBA, WBO and IBF heavyweight champion.
"I've spoken to Alex Krassyuk a few weeks ago and he believes Martin Bakole outside of Tyson Fury is the toughest opponent and the toughest fighter out there which says everything about what he can do in the division," Shalom said.
"We have to hope that this unification gets made and things can start moving because I think that every fighter in the heavyweight division dreams of becoming a world champion, wants to fight for a world title and I think that's why everyone's hoping that this gets made, and if it doesn't then we move on quickly."