Former world heavyweight boxing champion David Haye is set to announce his retirement.
The Londoner informed the British Boxing Board of Control he did not want to renew his licence.
Haye, who celebrates his 31st birthday on Thursday, always said he would not fight on past the age of 30.
However, many expected the Briton would delay his decision for at least one more big fight, possibly against Ukraine's Vitali Klitschko.
His last fight was against Klitschko's brother, Wladimir, last July when he lost his WBA world title by an unanimous points decision in Hamburg.
Haye had been strongly linked with a comeback bout against Vitali, who holds the WBC title.
Board secretary Robert Smith told BBC Radio 5 live that his organisation had received an email from Haye stating he did not want to renew his boxing licence.
He said: "According to the email I received, he is no longer wishing to renew his licence."
Asked whether he had thought a Haye-Klitschko rematch had been likely, Smith added: "It doesn't really matter what I think, it's up to David and Adam (Booth, Haye's trainer and manager). Obviously his last fight must have been bitterly disappointing for him, but if you look at his career as a whole he has been very good to the sport and we wish him well.
"There are many instances when heavyweights can go on longer than the smaller weight divisions but he has his whole life ahead of him, he has achieved a great deal and good luck to the man.
"You dedicate your life to your sport and to find something after that endeavour is very difficult for anybody."
Haye's last fight against the Klitschko, held in Hamburg, was a heavyweight unification fight for the WBA, WBO, IBF and IBO heavyweight titles.
The three judges scored the bout 117-109, 118-108 and 116-110, all in Klitschko's favour.
Haye first won the WBA belt by beating giant Russian Nikolay Valuev on points in Germany in November 2009.
The former cruiserweight king, who has lost only twice in 27 professional bouts, then defended his title by stopping American John Ruiz at the MEN Arena the following April.
Haye also defended his title against fellow Brit Audley Harrison with a devastating third-round stoppage, also in Manchester.
Boxing promoter Barry Hearn, chairman of Leyton Orient football club, told Sky Sports News:
"David has plans outside of the sport and I wish him all the best. He was a credit to British boxing.
"I believe he is looking at a movie career and he's a good looking lad. He will not go down as one of the all time greats and he was never really big enough to be a heavyweight.
"But he fought some big lads and you cannot doubt his bravery."