It had been hoped that Joshua, who holds the IBF, WBA and WBO belts, and Wilder would be able to arrange a unification title fight before the end of the year, with the winner being the first man to hold all four world heavyweight belts.
However, those plans have been scuppered with the WBA ordering Joshua to agree a fight with their mandatory challenger Alexander Povetkin, or be risk being stripped of the title.
That means that any fight with Wilder will have to wait, something the American is less than impressed with.
In an expletive-laden tweet, Wilder said: “I knew I smelt p***** but damn Anthony Joshua I didn’t know the odor was that strong you coward ass b****. Had the world waiting for 3 months playing games just for this moment.
“You’re not a true champion!! You’re just a weak minded coward that’s holding hard metal. #Facts.”
He added: “All they had to do is say they were scared to fight. Period. But instead they made themselves look like what they are, not stand up guys.
“I'm so happy it's over now I've done my part the world seen that so stay in England.”
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