Klitschko, trapped on the stairs, hit back by telling the Englishman to " behave himself" but, significantly, he left the door open for a fight between the pair in the future.

He told 27-year-old Londoner Haye that he could get his chance to try and emulate his hero Evander Holyfield, who graduated from cruiserweight to heavyweight champion, once he has established himself in the higher division.

Klitschko is committed to a mandatory defence of his WBO title against American Tony Thompson in Hamburg on July 12 and has then been ordered to face Alexander Povetkin, his number one IBF challenger.

But Haye, staring into his face, shouted: "I don't want you to lose to these two bums.

"I am the undisputed number one champion in the cruiserweight division. If you want to fight the number one fighter then fight me."

Klitschko countered: "For now, in the heavyweight division you are a nobody. You have to prove yourself."

But Haye told him: "The last time an undisputed champion went up to heavyweight he won the title - Evander Holyfield. I'm bigger than Evander Holyfield."

Klitschko, struggling to get a word in, repeated: "You have to prove yourself. You haven't proved anything."

Haye responded: "I don't have anything to prove. You've got to fight the best fighters out there - and the best fighter is me.

"Who's Tony Thompson? What have Thompson and Alexander Povetkin ever done?

"These people are bums. Fight the main man, that's me. There is no need to hide behind these mandatory bums. No-one knows who they are.

"When your mandatories are out of the way then let's get it on. I'll beat two top 10 fighters, then what are we going to do?"