Lennox Lewis will still fight Vitali Klitschko for the WBC world heavyweight title in April, the Ukrainian boxer's promoter told BBC Sport.

Promoter's spokesman Rainer Koppke said the fight would go ahead, contrary to reports that Lewis wanted a lucrative rematch with Mike Tyson.

"I really believe in this fight," Koppke told BBC World Service.

"We don't have any problems with the deal or the fight.

Boxing fans would be much more interested in a fight with Vitali Promoter's spokesman Rainer Koppke

"I don't think that Lennox Lewis is scared of Vitali, but I do think he wants more money.

"It's all just a question of money."

Klitschko is the number one-rated contender for the belt.

But some reports suggest that Lewis could earn $25m (�15.3m) for a fight against Tyson as opposed to $10m to face Klitschko.

"After the last Lewis-Tyson fight, Tyson said he had no chance of beating him [Lewis]," said Koppke.

"So boxing fans would be much more interested in a fight with Vitali."

Promoter Universum Box-Promotion have not ruled out taking legal action should Lewis back out of the contract.

"We might sue, or the WBC might decide that Lewis should retire if he doesn't want to fight the top contender," said Koppke.

The Lewis-Klitschko fight is scheduled to take place on 12 April in Las Vegas or 19 April in New York

Lewis stopped Tyson in the eighth round of their heavyweight championship fight on 8 June last year and has not fought since.