(CNN) -- World heavyweight champion Wladimir Klitschko has told reporters that he believes rival David Haye is only bluffing with his threats to quit boxing in October.
International Boxing Federation (IBF) and World Boxing Organization (WBO) champion Klitschko will defend his titles against Dereck Chisora on April 30, prompting World Boxing Association (WBA) champion Haye to announce that the unification fight between the duo will now not happen because he intends to retire when he turns 31 later this year.
But Ukrainian Klitschko has poured scorn on Haye's claims, saying: "This is total nonsense and he is playing the media.
"He will not retire because he is a liar. He has no legacy whatsoever from boxing -- beating Audley Harrison has not given him a legacy.
"David Haye has accomplished nothing in the heavyweight division other than to present himself with his stupid t-shirt and comments," Klitschko continued.
"This guy will eventually fight me because everything coming out of his mouth is a lie, but if he does retire, he will be a loser with no legacy in the heavyweight division at all."
Haye made the comments after Klitschko chose to honor an agreement to face the Briton's compatriot Chisora, in a fight that was postponed from last year after Klitschko suffered a back injury in training.
However, Klitschko maintains that if he beats Chisora, he can still fight Haye later in the year.
The Ukrainian added: "I don't need a half a year to prepare for Haye. Me facing Chisora first is good promotion for the fight because the guy is also British and also very loud."
Haye could be forced to fight mandatory WBA challenger and former world champion Ruslan Chagaev, with a preliminary date set for July 2, although Klitshcko maintains that could be side-stepped.
"I don't take David Haye as a super-special fight. I'm always in shape anyway. He could give Chagaev step-aside money and then I'm going to be there with nobody to fight," continued Klitschko.
"Because of our history before, I would fight him on July 2 and we would work on the contract, but I would still fight Chisora first."