Eddie Hearn does not believe "deluded" Deontay Wilder wants a lucrative heavyweight unification fight with Anthony Joshua and urged the American to "stick to the facts".
Hearn, Joshua's promoter, revealed that Wilder has not yet signed a contract which he was sent last week.
The WBC heavyweight champion stated that he would be prepared to fight Joshua in the UK and a $50million offer to step into the ring with the Brit in the United States also remains on the table.
Hearn has stirred the pot by questioning whether Wilder has a genuine desire to do battle with the WBO, IBF, IBO and WBA strap-holder.
"Let's just stick to facts. We made them an offer firstly, they didn't even reply," the Matchroom Boxing boss told Sky Sports.
"They made us an offer, we asked to see a contract, they refused to send one. We made them another offer, after nearly four weeks they accepted and asked for a contract and we sent them one. If they want the fight they will sign it."
Hearn added: "I can't quite make out whether people are lying to Deontay about the negotiations or he is just completely deluded.
"I saw an interview with him yesterday saying he is actually two people, Deontay Wilder and The Bronze Bomber, so I'm siding with deluded. It's not complicated - we have set out the terms of the deal, we put it in a contract and sent it to him.
"He has now had the contract a week. We are getting calls from the WBA on a daily basis asking what's happening, there is absolutely zero urgency from Deontay and his team other than posting silly Instagram videos.
"The proof is in the resumes and at this stage I believe Deontay and his team do not want this fight."
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