WBC heavyweight champion Deontay Wilder has offered $50m (£35.9m) for a unification fight with WBO, IBF and WBA titles holder Anthony Joshua.
American Wilder posted a video on Twitter which shows Joshua saying he would accept the fight for $50m.
Wilder said “all the money is in the bag so I expect you will be a man of your word”.
Meanwhile, Wilder’s manager Shelly Finkel confirmed to ESPN that an offer had been made.
Finkel also said the offer contains no rematch clause and that it would be the next fight for each boxer, taking place between September and December at a venue of Wilder’s choosing.
However, Joshua’s promoter Eddie Hearn said earlier this month that the WBA has ordered the Briton to enter into negotiations with mandatory challenger Alexander Povetkin.
Wilder added: “Tell Eddie Hearn to let you personally check his email this time. By the way, I sent your manager Rob McCracken the email as well.
“I am looking forward to our meeting in the ring.”
Unbeaten Joshua added the WBO belt to his collection after a unanimous points win over Joseph Parker in Cardiff on 1 April, while Wilder beat Luis Ortiz in his last fight in March.