David Haye has goaded Wladimir Klitschko by unveiling a poster depicting him decapitating his heavyweight rival.

Just a week after Klitschko dared Haye to once again wear the infamous T-shirt of him holding aloft the severed heads of the Ukrainian and his brother Vitali, the WBA champion resumed his taunting.

Far from regretting the T-shirt, as Klitschko claims, Haye declared it was a stroke of genius that has been of enormous benefit to his career.

And the 30-year-old sought to reopen old wounds ahead of their showdown in Hamburg on July 2 by unfurling his gruesomely bloody poster at today's open workout in London.

"In 2009 I came out with the T-shirt showing me with the Klitschkos' heads in my hands. Now things have changed," he said.

"Wladimir dared me to wear that T-shirt again but instead, I've gone one better.

"I've released an I-Phone game called 'David Haye's Knockout'. It lets you knock an anonymous Eastern European's head off.

"I know it will get under his skin big time when he finds out how popular it's been and how many downloads there are.

"Do I regret that T-shirt? Hell no! No way! It was one of the best things I've ever done.

"That decapitation T-shirt was one of the smartest business moves I've ever made."

Klitschko has been on a charm offensive since the fight was announced and many believe he has been winning the PR battle in the build-up to the eagerly awaited unification clash.

In contrast, Haye has been uncharacteristically subdued - until his typically belligerent performance.

He warned the public not to be duped by the IBF, WBO and IBO champion and stressed the 35-year-old's education - he has a doctorate degree in sports science - will be worthless in the ring.

"Wladimir's been going beyond the call of duty trying to be everyone's friend and as charming as possible," he said.

"But none of that will help him when the first bell rings. It won't matter how intelligent he is. The 18 languages won't help him either.

"Who cares about all of that? The best fighter wins. Who cares how charming he is.

"I've noticed he's been making a big effort with the charm.

"He's clearly changed his personality and tried to get away from the Dolph Lundgren, Ivan Drago Rocky IV character.

"He's trying to be more friendly, but it's an act - he is Ivan Drago. He's just been sprinkling on some cheese and charm."

Haye mocked Klitschko's claim that many British supporters will be cheering him on when the rivals collide at the Imtech Arena.

"No one from the UK will be paying hard earned money to go over there and cheer for him, that's guaranteed," said Haye.

"I don't know where he thinks this British support is going to come from.

"He will come out to a chorus of boos on July 2 and he better be ready for that."

Haye reiterated that his retirement date of October 13 - his 31st birthday - is set in stone and is adamant his mind will not be changed by the prospect of meeting Vitali.

"Vitali has to fight in September so it looks pretty unlikely that I will meet him," he said.

"If that's the case then this will probably be my last fight, so I have to make sure I go out with a bang and with my career best performance.

"You have to leave people wanting more. I love people who go out on their own terms, not because doctors are saying they can't box any more.

"There will always one big fight left out there. I could fight the whole top 10 but then there would be a whole new top 10.

"There is always someone making noise in this sport. You have to find the best man in the sport and beat him and go out on your own terms."