Carl Froch has been ordered to give domestic rival George Groves a rematch within 90 days or be stripped of his world title by the International Boxing Federation.
Froch claimed on Friday that Groves rejected "a seven-figure sum" for a second chance after their controversial fight in November, which the champion won with a contentious ninth-round stoppage to keep his WBA and IBF belts.
Groves admits he has turned down an offer but is adamant he is as eager as ever to get back into the ring with Froch, and his cause has been helped after the IBF decided the bout was controversial enough to merit an immediate rematch.
Lindsey Tucker, the IBF championships chairman, told Press Association Sport: "We have ordered an immediate rematch between Carl Froch and George Groves.
"After a fight our rules say a boxer has 10 days to file an appeal. Groves did that, and at a hearing on January 15 in Newark we had a three-man panel review all of the evidence and they came back with the decision we must order a rematch.
"The 90 day period starts from Friday, January 24 and I'm pretty sure Carl Froch will have already received notification.
"If he fails to defend the belt against Groves within this period it's more than likely he will lose his title.
"The fighters and their teams have a certain amount of time to come to an agreement and if they can't, it will come down to purse bids."
Tucker added: "If for some reason Froch gave up the title then we would order the two highest-rated guys to fight for the vacant belt.
"Since we already ordered Groves to fight Froch, he would be likely to be one of the guys to fight for that vacant title."
Groves said on Twitter: "Oh Dear! IBF order IMMEDIATE rematch with me and @Carl_Froch ... Maybe I was right after all turning down that 'amazing' 7 figure offer haha.
"Now everyone understands @Carl_Froch press release today.. Wants to move on? Hold on honey IBF says #NoNoNo #RematchOrVacate haha."
Underdog Groves, 25, had Froch down in the first round of their November bout and was ahead on the scorecard when the veteran champion rallied and forced a contentious ninth-round stoppage in Manchester last year.
Both Groves and the British public immediately called for a rematch which Froch seemed to consider only grudgingly. However, the Nottingham man insisted on Friday he has given the Londoner a shot at revenge.
"There has been plenty of speculation over the last few weeks regarding my future," Froch said.
"As it stands we are looking closely at two options - George Groves and Julio Cesar Chavez Jnr.
"Yesterday, we made a seven figure offer to George Groves for a second fight that would have seen him earn around double that of the first.
"Disappointingly, George rejected this offer so we are continuing our talks with (Chavez Jnr's promoters) Top Rank and (American broadcaster) HBO regarding Chavez Jnr.
"I understand the demand for the Groves fight in the UK, but also the demand in the US for the Chavez fight.
"Talks are ongoing and no doubt some further news will break soon. I'm happy to fight anyone, as I have done throughout my entire career."
Hammersmith fighter Groves responded: "I am unsure why Carl Froch has today released a statement implying I do not wish to take the fight, as I was under the impression we are still in negotiations.
"The Matchroom offer in question came with many stipulations and options I felt were unsatisfactory.
"I am currently awaiting an improved offer from his promoter, as well as speaking to other promoters interested in promoting this fight."
Groves, who felt referee Howard Foster stopped the fight too early when Froch had him briefly in trouble, added: "If I didn't want to fight Carl Froch then I wouldn't have invested so much time and money into appealing with the IBF over the dubious outcome of the first fight.
"And I await the outcome of that hearing in the very near future."