Wladimir Klitschko has revealed he intends to go to court over the negotiations for his rematch against Tyson Fury.
Having lost the WBA, WBO and IBF titles to Fury last November, the 40-year-old has the right to a rematch, with the initial fight scheduled for July postponed due after Fury suffered an ankle injury.
A new date, October 29, has been set for Manchester Arena but Klitschko posted a video on Twitter on Wednesday morning claiming Fury's camp has attempted to shift the goalposts of their agreement and is therefore seeking legal action.
"Dear fans, I just want to keep you updated on the status quo of my rematch against Fury," the Ukrainian said.
"Unfortunately, team Fury is trying to change the terms of an already-signed contract multiple times and it is going on endless. (sic)
"To protect my own rights and eventually see the rematch, I am forced to go to court."
Shortly after the video was posted, Klitschko's manager Bernd Boente explained why it was deemed necessary to take Fury's team to court.
— Klitschko (@Klitschko) August 17, 2016
"They want to change details in the contract," he told Boxing News.
"Obviously we cannot discuss that publicly - but, as you know, we've already done press conferences in Manchester, in Cologne.
"Now team Fury wants to change many parts of the contract, important parts, financial conditions etc, etc. and now I think we have to make sure that we implement our rights and so we have to go to court in Germany because the contract is under German jurisdiction.
"We have enforced our rights, and that is what we will do now."
Team Fury were unavailable for comment.
Fury, who earlier this week mapped out his plans for his next three fights which included beating Klitschko and then facing unification bouts against Anthony Joshua and Deontay Wilder, suffered a badly-sprained ankle in June which saw the rematch postponed.
He is also contending with doping allegations after UK Anti-Doping charged the 28-year-old over the alleged presence of a banned substance.
Both Fury, and his cousin Hughie, have a hearing on November 4 having strenuously denied the charge.
A provisional suspension imposed on June 24 has been lifted after an appeal.