World heavyweight champion Vladimir Klitschko has called off his April 30 fight against Commonwealth champion Dereck Chisora after failing to recover in time from an injury sustained in December.

"I am very sorry for this final cancellation especially for the fans who had sold out the SAP Arena (in Mannheim)," said Ukrainian Klitschko, the IBF, IBO and WBO champion.

"But I am convinced that I will soon stage another fight in Mannheim," added the Germany-based fighter, whose brother Vitaly holds the WBC crown.

The fight against Briton Chisora was originally scheduled for December but was postponed when Klitschko tore an abdominal muscle.

It is unclear whether Klitschko, once fit again, will reschedule the fight with the Briton or whether he will pick another challenger.

Medical tests showed that Klitschko had not fully recovered from the injury he had sustained in training and the April date was too soon for a fight.

"As things stand now it is difficult to predict when he will have fully recovered. A fight in April with all the intensive preparation he needs is too big a risk," said his doctor, Hans-Wilhelm Mueller-Wohlfahrt.

The 26-year-old Chisora beat Sam Sexton in September to add the Commonwealth heavyweight title to his British crown.

Zimbabwe-born Chisora has fought and won 14 fights, nine through knockout, compared to 34-year-old Klitschko's 55 wins and three defeats.

Reuters