Britainâs Anthony Joshua will meet Joseph Parker in a world heavyweight unification fight in Cardiff in March.
Joshua, 28, holds the IBF and WBA belts, while New Zealander Parker is the WBO champion.
Cardiffâs Principality stadium â where Joshua successfully defended his titles against Carlos Takam in October â will host the bout.
âIâm delighted to get this fight made â itâs been a long time coming,â said Joshuaâs promoter Eddie Hearn . âItâs the first time in history that two reigning heavyweight world champions have met in Britain.â
Joshua added: âThese fights arenât easy because there is a lot on the line â so respect to team Parker for taking the challenge .
âIâm looking forward to it. Training camp is under way and before you know, 31 March will be upon us.
Parkerâs representative *David Higgins* arrived in the UK last week to finalise a deal. Talks had previously stalled over how the purse would be split but a compromise was reached last month which will see Parker, 25, earn _*30-35%.*_
Parker is undefeated in his 24 professional fights, with 18 of those wins coming by a knockout.
âAnthony Joshua is in for a huge shock,â_ Parker said. âA couple of months ago I heard him say: âWhy should I be worried about this little kid from New Zealand?â
âWell, now heâs about to find out. And the world is about to find out whether AJ can really take a punch.â
Joshua became IBF heavyweight champion by defeating *Charles Martin* at Londonâs O2 Arena in April 2016.
The following April, he added the WBA belt by beating Wladimir Klitschko in front of 90,000 fans at Wembley Stadium.
Whoever wins in March is certain to then face undefeated American Deontay Wilder, who holds the fourth belt in the heavyweight division. No boxer has held all four heavyweight belts simultaneously.
Parkerâs camp have been pushing for the fight ever since Joshua defeated Takam last year.
They staged a news conference in November featuring clips of Joshua being knocked down in his amateur days and offered Â£20,000 to anyone with footage of him being floored.
That prompted Joshua to hit back, saying he was being âdemonisedâ by the Parker camp. But Higgins later told BBC Sport Joshua was ârattledâ.
Parker, who will fly to Las Vegas for nine weeks of training, told Radio 5 live that his news conference âplayed a big part in making the fight happenâ.
âHe got angry and upset, âsaid Parker. âEverything along the way helped, now we can put that behind us and get training.â
Parker says he and Joshua have found âcommon groundâ over the purse adding that he ârespectsâ the Londoner.
âThere is no animosity,â added the Kiwi. âI am a relaxed, calm person. I have respect for Joshua, you do not have a 20-0 record if you are not that good.
âBut I think I can beat anyone in the world, I would not be here if I did not believe in myself.â
On unifying the division, he added: âThe world needs one champion.â