Nigerian British boxer, Anthony Joshua could become the greatest boxer in the world by December.

The WBO, IBF and WBA titles holder, could unify all the belts if he beats WBC heavyweight champion, Deontay Wilder.

The challenger is offering $50million (which translates to about 18billion Naira) for a unification fight with Anthony Joshua.

American Wilder posted a video on Twitter, which shows Joshua saying he would accept the fight for $50m.

His manager, Shelly Finkel also confirmed that an offer has been made.

Finkel said the offer, which contains no rematch clause, is expected to take place between September and December at a venue that Wilder chooses.

However, Joshua has been ordered by the WBA to first fight mandatory challenger, Alexander Povetkin.

It has not been confirmed if Anthony Joshua's promoter Eddie Hearn can pull off these two fights before December.

Both Joshua and Wilder remain unbeaten.

Joshua added the WBO belt after winning his first fight by points over Joseph Parker in Cardiff on April 1, while Wilder beat Luis Ortiz in his last fight in March.