Anthony Joshua and promoter Eddie Hearn will meet American heavyweight Deontay Wilder and his team this Friday to discuss a $50m (£35.9m) unification fight offer made to the British boxer.
The unbeaten Wilder published a video in which he included a historical clip of Joshua requesting "$50m up front" to agree to the fight and inferred such an offer had been made.
Wilder's manager Shelly Finkel says the offer includes a $50m flat fee and a 50 per cent share of the revenue generated by a showdown between the heavyweight division's only remaining world title holders.
Hearn says a 50/50 split "isn't of interest" – he believes Joshua holds much more pulling power – in contrast to the $50m offer which "has to be taken seriously".
"I spoke to AJ and he knows the situation," said the Matchroom Boxing boss.
"He wants to know if it's real. We want to see the money, we want to know where it is and then we'll carry on talking.
"We've booked a meeting in for Friday. Is it a PR move? Is it real? We're going to find out. But if it is real it's definitely something we're going to take seriously."
Accepting Wilder's offer would likely mean the date and venue for the fight would be set by the American's team.
After beating Joseph Parker last month to secure the WBO belt, leaving him with just Wilder's WBC strap to claim before becoming the undisputed heavyweight champion, Joshua insisted he would want to fight him on UK soil.
Earlier this month Hearn contacted Wilder advisor Al Haymon with a $12.5m offer to come to the UK and fight, insisting that it represented "five times what Deontay Wilder has made for any fight".
If no deal is made with Wilder, Joshua's next fight is likely to be against mandatory WBA challenger Alexander Povetkin.