Tyson Fury is set to fight Oleksandr Usyk in an undisputed heavyweight showdown in Saudi Arabia.
Promoter Frank Warren said a deal for the blockbuster bout has finally been agreed on Friday, 29 September.
However, the date of the contest, which will take place in Riyadh, has not been announced.
“Delighted to finally get this fight signed,” said Queensbury promoter Warren. “This is the biggest fight that could possibly be made in our sport.
“The heavyweights always spark the imagination of the fans, and I have no doubt this will be the biggest boxing event of the century.”
Fury, 35, who lives in Morecambe, is due to fight in Riyadh against former UFC world heavyweight champion Francis Ngannou on 28 October. His WBC belt will not be on the line.
Last month, Usyk, 36 maintained his unbeaten record with a knockout victory over Daniel Dubois in Poland.
The Ukrainian put down Londoner Dubois in the ninth round to retain his WBA, IBF and WBO heavyweight belts.
The winner of the bout between Fury and Usyk will see the first undisputed heavyweight champion of the four-belt era.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To know...