David Haye will again attempt to unify the heavyweight division this year.
The 31-year-old, who last fought in July 2011 when he lost to WBA, IBF and WBO heavyweight champion Wladimir Klitschko, does not currently hold a British boxing licence after announcing his retirement six months ago.
However, he has decided to come out of retirement and is targeting world domination after his fight with Dereck Chisora on July 14.
Haye explained: "That fight will happen, but in September at the earliest.
"If it could have been agreed already I wouldn't be fighting Chisora.
"I have always been looking for that fight against the Klitschkos. That's the one thing I've got left to do - to unify the titles."
Haye won 25 of his 27 professional bouts - 23 by knockout.