Klitschko is out to reclaim his lost titles.
White admits talks are "progressing" but an imminent announcement appears unlikely.
Coatbridge fighter relinquished his WBA belt after being outclassed in super-lightweight unification bout.
Klitschko tells of his burning desire to take Joshua's belts.
"I've got kids at York Hall who would beat McGregor hands down," says Matchroom promoter.
The 30-year-old will reveal his next opponent after Ramadan.
Joshua believes he has five years until he becomes one of the best fighters in the world.
Franchise president feels obligated to give McGregor the chance to face American boxer.
But current light heavyweight champion urges UFC superstar to taken any deal to fight unbeaten boxer.
Wilder has hinted at his desire to get in the ring with Joshua.
Both MMA fighters and boxers are keen to capitalise on the cross-code hype.
British heavyweight interested in 'mega event' boxing match against heavy-hitting UFC veteran.
Boltonian believes he would win a boxing contest against UFC star amid ongoing Floyd Mayweather speculation.
Haye's ambitions of fighting Joshua were dashed by Bellew.
Terry Flanagan and a move up to light-welterweight are among his options.
Crolla and Linares are to face off at the Manchester Arena.
UFC superstar promises to cause a 'shock' but refuses to confirm possible date.
British boxer says he is looking after his own business affairs after series of betrayals.
World Series Boxing clash with Italy in York will go ahead despite team watching harrowing events.
Californian wants additional cross-code bout against former heavyweight boxing champion.
GGG wants to unify middleweight division after knockout streak ends against Daniel Jacobs.
McGregor holds an exclusive contract with UFC and will need permission to fight Mayweather in a boxing match.
Decorated Mexican boxer joins Canelo Alvarez and Oscar De La Hoya in opposing cross-sport bout.
McGregor's last fight was when he defeated Eddie Alvarez at UFC 205 in November 2016.
American open to rekindling his boxing career with or without the UFC superstar.
Shields' fight against Szilvia Szabados will be the first female boxing bout to headline a card on premium TV.
Charismatic New Yorker guided careers of 19 champions, including Evander Holyfield and Lennox Lewis.
Jack lined up to face WBA light heavyweight champion Cleverly.
MMA fighter-turned-analyst believes 'Money' no longer has enough athletes to create stories.
22-year-old Fury will fight in New Zealand on 6 May.