Bernd Bonte told Setanta Sports News Klitschko had received numerous offers to replace Haye (22-1) for the June 20 clash but that delaying the fight or facing WBA champion-in-recess Chagaev (25-0-1) were the only options being considered.

"It’s still a possibility (fighting Haye) but our first priority is Chagaev, but that fight is not a done deal," Bonte said. "Chagaev would be a big fight. It would be for The Ring belt. I have got confirmation from The Ring (magazine)."

"At the moment we are only interested in Chagaev or Haye on June 20 or three weeks later," he added.

The Ring title can be claimed by the winner of a bout between the magazine’s top-ranked boxer in any weight class and the number two or three contender based on rigid criteria.

Haye’s manager Adam Booth told Setanta Haye had suffered a deteriorating back injury in training requiring "aggressive physiotherapy" and that forced the cancellation of the fight.

"David will be fit and ready to fight, to step in the ring, on July 11," Booth added.

"They can just hold up their training and fight David three weeks later, three weeks is nothing in the scheme of things."

Undefeated Chagaev was due to fight Russian Nikolai Valuev (50-1) in Finland for the WBA title Saturday but the fight was called off after the contract was not fulfilled.

A source told Reuters Chagaev had tested positive for hepatitis B.