Barry Hearn, the founder of Matchroom, says a contract is still on the table for WBC heavyweight champion Deontay Wilder (40-0, 39 KOs) - should he want to face IBF, IBO, WBA, WBO Anthony Joshua (21-0, 20 KOs).

The elder Hearn, who promotes Joshua, says all of the terms are on the table. The two sides were negotiating the terms for a potential fight in the fall, but their negotiations fell apart after the WBA ordered Joshua to make a mandatory defense against once-beaten Alexander Povetkin of Russia.

"There is a contract on [Wilder's] people's desk which says: April 13, 2019, Wembley Stadium," Matchroom chairman Hearn told Sky Sports News. "The contract encapsulates all the terms that you agreed. There's only one thing that you've got to do - sign the contract."

Barry Hearn believes Wilder is jealous of Joshua's success.

Joshua has been drawing record crowds in the UK, as high as 90,000 fans, to his most recent fights.

Because of his drawing power, the popular British star is earning significantly more money per fight than Wilder is securing in the United States.

"Boxing hadn't gone anywhere for 10 years but suddenly it is as hot as hell - it is a sexy sport. We need to keep coming up with big fights, and there's nothing bigger than Anthony Joshua. We appreciate Wilder isn't making any money. He probably looks at Joshua with a good degree of jealousy," Barry Hearn said.

"'I'm the biggest name in America but I'm earning less than a tenth of what Anthony earns per fight'. Wilder has something in front of him where he can plan his future. He can earn five or six times more than he's ever earned in his life.

"And if he's good enough, he's got all the cookies. Unbelievable! He will be massive. There's one obstacle: Anthony Joshua."