The British heavyweight champions are set to clash in a mouth-watering fight but Haye admits that he will be stunned if it happens before November and it would require a "ridiculous offer" for the event to take place at the planned date this summer.
The former world champion told Sky Sports: "I'll be surprised if it happens before November. If it does happen before November, fantastic.
"Knowing boxing like I do, whatever offer they receive it's going to need to be ridiculous, absolutely ridiculous to get it over the line, and if it does get over the line, God bless both of them.
"They deserve every penny they earn, because they've both put it on the line. They've both sacrificed, they've both become heavyweight world champion in their own right.
"They both deserve to be in this big mega event. May the best man win when it finally does happen."
Reports have suggested that a deal for the bout is drawing ever closer and promoter Eddie Hearn said both camps were "nearly there" in terms of confirming the date and venue of the fight.
He said: "We're in a good place, nice and close. I can't do any more than I'm doing. People know that we're on the verge.
"Both guys are desperate to get moving. Joshua wants a date for the start of his camp. This is the sporting event of 2021.
"One lucky site will get good news next week and the whole world will stop to watch this fight."