Speculation about a blockbuster bout between the British pair has been steadily building since Fury dethroned Deontay Wilder to become WBC heavyweight champion, with Joshua regaining his WBA, IBF and WBO titles by outpointing Andy Ruiz in their rematch last December.
And while Hearn insists there are a number of obstacles to overcome, Joshua's promoter revealed the fighters are "in agreement regarding the financial terms of the fight" and that their first meeting will take place next year.
"We're making great progress," Hearn told Sky Sports News. "There is still a lot to overcome. We are looking at venues and dates. It's fair to say (Joshua and Fury) are in agreement regarding the financial terms of the fight.
"The main positive news is that Joshua and Fury have agreed to a two-fight deal, in essence. The most difficult part of any deal is the financial element. I believe we're in a great place where both guys have agreed to what that should be.
"We have not signed contracts because there are still things to be worked out. We're pushing towards a place where they can be drafted, for 2021. Both guys are in agreement. The structure of the deal has been put forward, and agreed to by both parties."
Who would win this all-British heavyweight clash?