Dillian Whyte’s suspension has been lifted by the WBC, after he was cleared by UK Anti-Doping last week.
The British heavyweight is reinstated as WBC interim champion and will receive a mandatory shot at the full title, currently held by Deontay Wilder, in February 2021.
Whyte has been ranked at No 1 by the governing body since October 2017 but has never received an opportunity at a world championship.
He became mandatory challenger by defeating Oscar Rivas earlier this year but allegations of an "adverse finding" in a UKAD test meant his status was suspended by the WBC - in the past week he has been cleared, defeated Mariusz Wach and is now reinstated.
However, his wait for a world title fight will go on because Wilder next plans a rematch against Tyson Fury (who is currently regarded as his mandatory challenger) in February.
A WBC statement said: "Based on a limited but detailed investigation and after collecting information, including the WBC's consultation with two independent experts, concluded that there was insufficient evidence that Mr. Whyte intentionally ingested a prohibited substance in order to improve his performance. In light of the WBC's own finding and the withdrawal of UKAD charges against Mr. Whyte, the WBC has closed its internal investigation.
"The WBC lifts its provisional suspension and confirms Mr. Whyte's recognition as WBC interim world champion.
"Interim champion Whyte will become the mandatory challenger of the division immediately after the mandatory defence of champion Deontay Wilder against the current one mandatory challenger Tyson Fury. The mandatory defence against Whyte must be carried out before February 2021."
He told Sky Sports News on Sunday about being cleared by UKAD: "As a nation we are quick to write each other and drag each other's names through the mud. We are sitting, hoping and waiting for something negative to bring someone down.
"Everyone was quick to throw me in a hole with no evidence and no facts.
"The facts are that I'm clean, I've always been clean and I've always been innocent.
"People who had nothing to gain were saying stuff just for the sake of it. Everyone has an opinion. Now I can say things, I will let people know I feel - everyone who belittled me and discredited my name. I will be really rude to those people.
"My last two fights have been hell - I won them, but they were hell.
"The Rivas fight? I didn't sleep for 48 hours before. I couldn't sleep because I knew what was going on. I'd sold tickets and wondered if the show would go on.
"Pure madness, pure madness. It was crazy.
"It blew my mind, big time. I don't know who I fought and beat. It shows how tough I am, brave I am and good I am. I had the ability to put things to the back of my mind and get the job done. I wasn't 100 per cent focused but I still got it done."
Whyte has since called Wilder a "coward, chicken, yellow-livered hill-billy" and said "I can knock him out".
Undefeated Wilder also has the prospect of an undisputed heavyweight championship fight with Anthony Joshua, who regained the IBF, WBA and WBO belts from Andy Ruiz Jr last weekend, back on the table.
WBC president Mauricio Sulaiman said: "Well it's back to the drawing board. Deontay Wilder has been ready to fight Anthony Joshua for a couple of years.
"Now Joshua has won his belts back there is the opportunity for a unification, and to have one champion in the heavyweight division."
Sulaiman said about Joshua's win over Ruiz Jr: "He prepared to fight 12 rounds coming out with the belts and he did.
"It was not an entertaining crowd-pleasing fight, but convincing for Joshua. He was smart and didn't let emotion get in the way.
"Deontay Wilder is unquestionably the best heavyweight. His recent fight and one punch KO puts that in perspective.
"He has 42 wins, one draw, 41 KOs, 10 defences. He is always willing to face whoever is the best to fight him, and I'm just very proud of Deontay Wilder!"
Joshua told Sky Sports News about facing Wilder: "I'm ready. I've got my belts back and I'm ready to fight him. But I'm not looking too far into the future because it takes your eyes off what is front of you.
"I take it step by step and, by the time I get to unification, I will be ready.
"I'll knock them down one by one and, when the big boys are ready, I'll be ready to become the next undisputed champion of the world.
"I really want to make that happen."
IBF mandatory challenger Kubrat Pulev is leading the race to be Joshua's next opponent, promoter Eddie Hearn confirmed earlier this week.