Oleksandr Usyk’s proposed fight with Joe Joyce is being held up by discussions over the purse split for the bout.
Joyce and Usyk are in negotiations to fight one another for the interim WBO title as they wait for the resolution of any fight between Anthony Joshua and Tyson Fury.
The Ukranian is currently the WBO mandatory challenger, and Alexander Krassyuk - Usyk’s promoter - wants the WBO to give clarity over how the purse should be split between the two fighters.
Krussyuk told Sky Sports: "The problem is that there is no frame for negotiations as the split has not been officially confirmed by the WBO.
"The split should be defined as the average of the last three fights of both fighters.
"And according to my knowledge, it should look like 93 per cent in favour of Usyk.
"The minimum allowed by the WBO is 80/20.
"Unless the split is officially fixed, any negotiations make no sense as they would not lead to an agreement."
Krassyuk has since said: "The WBO is a well-respected sanctioning body where I am honoured to be a member for many years as are many other promoters.
"[WBO president] Paco Valcarcel is a very fair and reasonable man, but the purse split is a matter of mathematics, not of anything else.
"The calculation is very simple. Three last declared purses of Usyk plus three last declared purses of Joyce equals the total pot. Usyk's purse divided to the total pot multiplied by 100 percent equals his percentage."