The WBO and WBA heavyweight champion, Tyson Fury is due to face Klitschko on October 29 at Manchester Arena.
But the Ukrainian’s team are preparing to take Fury to court as the British fighter wants to change the signed contracts for the fight with “unacceptable” demands for more money.
Klitschko’s team also want VADA (Voluntary Anti-Doping Association) testing after Fury’s suspension by UK Anti-Doping following an alleged failed drugs test in February 2015, although Fury categorically denies taking anything illegal.
Vada is an independent programme for boxing and mixed martial arts that provides random testing, but Fury is already under such terms with UKAD.
The bout was due to take place on July 9, but Fury withdrew with an ankle injury before it later emerged he was also suspended by UKAD.
Bernd Bonte, Klitschko’s manager, has claimed Fury’s team are now trying to back out of the fight.
He told Starsport: “Before everything was fine, we had signed the agreement many months ago.
“Now the Fury team – in my gut feeling – are trying to find ways to get out of the fight. All the contracts are signed, they were happy with it. Suddenly they want to renegotiate and have impossible demands and we have to make sure that we implement our rights to go through with the fight.
“They want to change everything and my feeling is that they want to get out of the fight.
“The demands are ridiculous, absolutely unacceptable.
“It is a bit strange that suddenly now when there is the investigation by UKAD, the upcoming hearing, then the injury and suddenly they ask for absolutely unacceptable terms.”
Klitschko’s team will take the matter to a German court as the fight contract was signed under law there.
Team Fury were unavailable for comment when contacted yesterday, but Starsport understands both sides are hopeful the matter will be resolved in the coming days.