Haye, who defeated giant Russian Nikolay Valuev in November, first faces a mandatory defence against American John Ruiz.

BBC: Bernard Hopkins targets David Haye title shot

Haye, 29, won the WBA belt by beating giant Russian Nikolay Valuev on points in Germany on 7 November 2009.

BBC: WBA champion David Haye to fight Audley Harrison

Haye took the WBA title by outpointing Russian Nikolay Valuev on Saturday.

BBC: Haye & Klitschko target showdown

The Helenius-Gammer fight was set to take place on the undercard of the WBA heavyweight title bout between holder Nikolay Valuev and Ruslan Chagaev.

BBC: Gammer retires following defeat

Talks were then held about an autumn challenge against Vitali until Haye's camp walked away and fought Nikolay Valuev for the WBA belt instead.

BBC: David Haye set to start talks with Klitschko brothers

The Englishman was set to fight Wladimir last year but pulled out with a back injury, later beating Nikolay Valuev to secure the WBA crown.

BBC: Haye and Klitschkos' US promoters talk in Las Vegas

What would happen against Britain's David Haye or Russian Nikolay Valuev?

BBC: What next for Audley Harrison?

First the Londoner must hope that Nikolay Valuev, the man he beat to win his title last November, will not enforce a rematch clause in their contract.

BBC: David Haye intent on unifying heavyweight division

He lost it again to James Toney by unanimous decision in April 2005 but the result was rescinded after Toney tested positive for a banned substance and Ruiz retained the belt as the fight went down as a no contest, only for him to lose it for the final time to Nikolay Valuev eight months later.

BBC: Ex-champion John Ruiz hangs up gloves