Manchester's Tom Aspinall has been upgraded to undisputed heavyweight champion as the UFC announced Jon Jones had officially retired.
The decision, delivered by Dana White after a UFC Fight Night in Azerbaijan, brings to an end seven months of uncertainty in the heavyweight division.
Aspinall is just the third Briton to become a UFC champion and spent 19 months as interim champion.
"Jon Jones called us last night and retired," White said.
"Jon Jones is officially retired. Tom Aspinall is the heavyweight champion of the UFC.
"Do I regret the time that I gave [Jones to decide]? Listen, if you look at what he's accomplished in the sport, no."
Jones, 37, claimed the heavyweight title in March 2023 and fought Stipe Miocic last November, despite Aspinall claiming the interim belt the year before.
Aspinall campaigned for a fight with Jones but the American decided against accepting the UFC's offer.
Jones is considered one of the best mixed martial artists of all time but will turn 38 in July and said previously fighting Aspinall wouldn't add to his "legacy".
Aspinall reacted to the news on his social media, saying: "For you fans, it's time to get this heavyweight division going. An active undisputed champion."
The Englishman is expected to defend the title this summer or early autumn and is likely to face number-one contender Ciryl Gane.
Aspinall has not fought since July 2024 and has spent just three minutes and 22 seconds in the octagon since 2023.
"I obviously feel bad for Tom that he lost all that time and obviously money, but we'll make it up to him," said White.
"Tom Aspinall's a good guy. He's been incredible through this whole process.
"He's been willing to do anything, fight him anywhere at any time and do this, and now he's like 'I'll fight anybody - you tell me who and I'll fight them'."
Aspinall goes down in history as the longest-reigning interim champion in the UFC.
Uncertainty and desperate negotiations have left the division at a standstill for seven months and fans will be left wondering why the UFC let it go on for so long.
Since November, White has insisted again and again the fight between Aspinall and Jones would be made. It wasn't until the last two weeks that the UFC president finally seemed to signal they weren't going to be able to convince Jones.
But such is the power of the star, 'Bones' Jones was permitted to keep the belt despite a lengthy injury absence and was allowed to fight Miocic, a retiring legend, instead of Aspinall on his comeback.
These allowances were understandable in many ways given the circumstances, but it is also true they happened because Jones has earned his right to dictate.
But even his power has a limit and the UFC has reached it. Now the heavyweight division will open a new chapter, with an Englishman at the peak.
It is a seminal moment for UK MMA as Aspinall follows in the footsteps of Leon Edwards and Michael Bisping and becomes the first Briton to hold the UFC heavyweight title, arguably the most coveted title in MMA.
The Mancunian has played the devoted company man and should now be rewarded, although two-time title challenger Gane will not be an easy first defence.
Aspinall will feel his reign as undisputed champion won't officially start until the next time his hand is raised in the octagon.