A unification bout with WBC champion Wilder has been touted for WBA, IBF and WBO titleholder Joshua, who claimed the latter belt with a unanimous decision over Joseph Parker last month.
A clash between the two unbeaten boxers is the fight everyone wants to see and on Wednesday, American Wilder announced he had something in the mail for Joshua – a $50m offer.
"I got something special for you," Wilder tweeted. "And by the way, all the money's in the bag."
