Deontay Wilder believes Anthony Joshua should be "embarrassed" for his role in the failure to set up a fight between the pair.
Despite initial suggestions that a highly awaited unification fight was on the cards, an impasse has been reached in talks between the heavyweight duo's respective camps.
And Wilder (40-0, 39 KOs), who has instead moved forward for plans to fight Tyson Fury in November, has blamed Joshua (21-0, 20 KOs) for the failure to find an agreement.
"I'm done [with Joshua]," Wilder told Boxing Scene. "I'm done. I'm done. He disgusted everybody. He disgusted me. He should be embarrassed and he should be disgusted by himself for being a champion and conducting himself this way.
"No champion acts that way. No champion talks like they're not ready.
"As a champion, there's no such thing as not being ready when you have all these hungry lions out here ready to eat."
Earlier this week, Showtime Sports president Stephen Espinoza claimed on ESPN + show The Boxing Beat that an agreement between Fury and Wilder was close. Showtime would televise the proposed fight on either Nov. 10 or Nov. 17 from Las Vegas.
Joshua, the current holder of the IBF, WBA and WBO titles, will fight the dangerous Russian Alexander Povetkin on Sept. 22.
Victory over Povetkin (34-1, 24 KOs), coupled with a win for Wilder in any prospective fight against Fury, would only increase the pressure on the pair to make a deal for a unification showdown.