LONDON, United Kingdom (AFP) — Anthony Joshua will face Daniel Dubois in an all-British showdown for the International Boxing Federation (IBF) world heavyweight title on 21 September after Oleksandr Usyk confirmed he was vacating the belt, it was announced on Wednesday.

Usyk, 37, became the first heavyweight to hold the IBF, World Boxing Organization, World Boxing Association and World Boxing Confederation belts when he beat Tyson Fury on a split decision in Saudi Arabia last month.

The Ukrainian is set to face the British boxer in a rematch in December and is therefore unable to face Dubois, who would have been the mandatory challenger.

Usyk had previously requested that he not be stripped of the IBF belt so that he might still hold the title when he meets Fury again in Riyadh.

“Anthony and Daniel, I know the IBF title is important to you. It is my present to you on 21 September,” he said in a video posted on social media.

Britain’s Lennox Lewis was the last man to unify the major heavyweight belts — three at the time — prior to Usyk, in 1999.

Two-time world champion Joshua, 34, has 28 victories and three losses during his career while Dubois, 26, has won 21 of his 23 fights.

“I’ve been having Dubois on my mind for a while,” Joshua said.

“He’ll be on my mind for the next 12 weeks until I’ve got my hand raised.”

Joshua was asked whether the age gap was on his mind ahead of the bout in London.

“I feel fresh,” he said.

“I feel good. I don’t drink, I don’t smoke. That’s about it, that’s my only vice, socializing. I don’t get caught up in antics outside boxing. I use boxing to keep me on the straight and narrow.”

“Young fighters coming up, look after your bodies, look after your minds.”

Dubois said Joshua had been “the king for a long time.”

“On the night, I need to become the king slayer,” he added.

“That’s my goal, that’s the mission I have.”

“I’m ready to let my fists do the talking. A hundred percent ready to go, train like a beast. So bring it on.”