ANTHONY JOSHUA must fight Tyson Fury by the end of 2025.
That's the deadline set by AJ's promoter Eddie Hearn.
A super-fight between two generational stars of British boxing has been rumoured for several years but talks always stalled.
Joshua, 34, will challenge fellow Brit Daniel Dubois for the IBF heavyweight belt at Wembley on Saturday.
Meanwhile, Fury, 36, will take on Oleksandr Usyk, who holds the other three recognised world titles, to a rematch in December.
Hearn told the BBC: "I do think AJ-Fury will happen regardless of whether Fury wins or not.
"But the size of the fight depends on their next two results."
In June, Joshua urged Fury to fight him while both boxers are still "fresh" but said he will not "sit around and wait" for the Gypsy King.
Asked whether there is a deadline of next year, Matchroom's Hearn replied: "Yes, definitely.
"If AJ beats Dubois and Fury beats Usyk, you've got the biggest fight in the history of the sport ever.
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"If one loses and the other wins, it's still a monster fight."
Joshua has his eyes firmly set on climbing back to the top of the boxing world this weekend.
ANTHONY JOSHUA VS DANIEL DUBOIS: All the information you need ahead of huge world title fight at Wembley
If he beats Dubois he will emulate greats Muhammad Ali, Lennox Lewis, Vitali Klitschko and Evander Holyfield by becoming a three-time heavyweight world champion.
The pair had to be separated when the promotion got under way with Frank Warren finding himself between the two giants as security guards held them back during a head-to-head interview.
Dubois currently holds the IBF belt which Usyk relinquished in June, ending his reign as the first undisputed heavyweight champion for a quarter of a century after barely a month.
Usyk was forced to vacate the belt in order to honour the contracted rematch with Fury, who suffered his first career defeat to the unbeaten Ukrainian in May.
Joshua won his first world title in April 2016 with a second-round knockout win over Charles Martin.
After losing his unified titles to Andy Ruiz Jr in January 2019, he won the belts back from the Mexican boxer six months later.