The negotiations are underway for WBO, IBF, IBO, WBA heavyweight champion Oleksandr Usyk to make a mandatory defense against Daniel Dubois, who holds the WBA's 'regular' title.

Uysk had been in deep negotiations for an undisputed fight with WBC world champion Tyson Fury - but the contest fell apart after both sides were unable to agree on all terms.

The unbeaten champion from Ukraine was already under the gun, with three mandatory defenses hanging over his head.

First up is Dubois - and Usyk is ready and willing to face him in the UK.

"The closest opportunity for Usyk is the WBA mandatory so it's Daniel Dubois," Krassyuk said to Sky Sports.

"Yesterday I had a meeting with George Warren to discuss what we're going to do and what we're able to do. We're now working out opportunities and London or Manchester are one of the options we're working on. Maybe if we can find a solution we can make it in the UK."

For his end, Fury is possibly going to face Olympic silver medal winner Joe Joyce - who next month will defend the WBO interim-title against Zhang Zhelei. Coincidently, Joyce is also the WBO's mandatory challenger to Usyk.

While Fury has blamed Usyk for the contest falling apart, Usyk's promoter rejects that claim.

"You face the other contradiction in the champion himself, the team considers him RTG - random thought generator," Krassyuk said.

"It means he comes up with retirement, then he comes up with 20 fights a year, then he comes up with fighting for no money, donating everything, and then he comes back. It looks a bit awkward and a bit random."