Tyson Fury and Oleksandr Usyk's undisputed heavyweight title clash, which was being targeted for April 29 in London, is now officially off.In a statement given to talkSPORT’s Jim White, Usyk's promoter Alex Krassyuk confirmed that the fight had to be called off after Fury made increasingly unrealistic demands.The parties had previously agreed to a 70-30 split in Fury's favor. However, according to Krassyuk, 'The Gypsy King' tried to push the subsequent negotiations further in his favor.In light of the unfortunate news, boxing fans took to Twitter to express their wrath at the WBC heavyweight champion. Twitter user @sussexbythesea4 marked their support for Usyk and slammed Fury for being too greedy:"This is all on Fury. Got greedy. If they ever meet am going for usyk"sussex 🇺🇦@sussexbythesea4@SkySportsBoxing This is all on Fury. Got greedy. If they ever meet am going for usyk10@SkySportsBoxing This is all on Fury. Got greedy. If they ever meet am going for usykAnother user @mrshawzy scoffed at the possibility of 'The Gyspy King' fighting Derek Chisora for a fourth time instead of facing the Ukrainian:"Absolute bottle job Fury, be back to fighting Chisora for the 148th time"Mr ShawZy@mrshawzy@SkySportsBoxing Absolute bottle job Fury, be back to fighting Chisora for the 148th time140@SkySportsBoxing Absolute bottle job Fury, be back to fighting Chisora for the 148th timeTwitter user @Mc_Legend_Face stated that Fury was a disgrace to boxing:"Fury is a disgrace. He should vacate his belt... He has only fought Two top-ten heavyweights in the last 8 years! [Wilder & Whyte] since beating Klitschko - & denied Wlad a rematch!"Hello@Mc_Legend_Face@SkySportsBoxing Fury is a disgrace. He should vacate his belt 🦆🦆He has only fought TWO top ten heavyweights in the last 8 years! (Wilder & Whyte) since beating Klitschko - & denied Wlad a rematch!#TysonFraud25@SkySportsBoxing Fury is a disgrace. He should vacate his belt 🦆🦆He has only fought TWO top ten heavyweights in the last 8 years! (Wilder & Whyte) since beating Klitschko - & denied Wlad a rematch!#TysonFraudUser @windyrhino questioned Fury's legacy as a heavyweight champion, while @jayceonnyg suggested that maybe it was 'The Gypsy King' who ducked former two-time heavyweight champion Anthony Joshua.eric windross@windyrhino@SkySportsBoxing And people think fury is the greatest heavyweight in history!! He ducks more fights then he actually fights!!! Time to vacate his belt!!35@SkySportsBoxing And people think fury is the greatest heavyweight in history!! He ducks more fights then he actually fights!!! Time to vacate his belt!!Jayceon Johnson@jayceonnyg@SkySportsBoxing Another fight for fury that’s off I’m starting to wonder who really ducked between him & Joshua now12@SkySportsBoxing Another fight for fury that’s off I’m starting to wonder who really ducked between him & Joshua nowA rather skeptical user @vaclav_salek opined that maybe the WBC champion was simultaneously in talks with another high-profile fighter during the negotiations with Usyk.Washek07@vaclav_salek@SkySportsBoxing 100% Fury is was in secret negotiations with someone else maybe a Wilder 4 fight, Ngannou etc@SkySportsBoxing 100% Fury is was in secret negotiations with someone else maybe a Wilder 4 fight, Ngannou etcMike Tyson believes Tyson Fury is unbeatableBoxing legend Mike Tyson believes reigning WBC heavyweight champion Tyson Fury is as good as they come. According to 'Iron Mike', none of the current crop of heavyweights can beat 'The Gypsy King'. He told talkSPORT's Spencer Oliver:“Tyson Fury proved over and over again that he’s the best... I respect Deontay Wilder and Usyk with the most respect I possess... Tyson Fury is the champ, the reigning champ, and is gonna be the champ for a long time, if he chooses to be, unless we get some new guy up... Mr. [Joe] Joyce is a tough, durable guy. He’s not gonna do it. Nobody around us can do it yet.”The former undisputed heavyweight champion also gave his take on how Fury would approach a fight with unified champion Oleksandr Usyk:"I just think Tyson’s not gonna do what Anthony Joshua [did]. I think he’s just gonna go out and put a lot of pressure on him.”Tyson Fury currently holds a pro boxing record of 33-0-1. He boasts wins over many greats of his generation, including former WBC champion Deontay Wilder and former unified champion Wladimir Klitschko.Watch Tyson Fury's career highlights below: