Anthony Joshua is set to defend his world heavyweight championships against Kubrat Pulev on June 20.
The Tottenham Hotspur Stadium in London is the likeliest venue to stage Joshua's homecoming.
A deal is now in place and confirmation will come later on Monday.
The defence of his IBF, WBA and WBO titles will be Joshua's first fight on UK soil in nearly two years, since he beat Alexander Povetkin at Wembley. Last year he was beaten in New York by Andy Ruiz Jr then won a rematch in Saudi Arabia.
Joshua's sights are on an undisputed title fight against new WBC champion Tyson Fury, a mega occasion which would crown one ruler of the division, but he must first dispose of his mandatory challenger in Pulev. Fury will, meanwhile, have a third fight with Deontay Wilder expected in July.
"I'm ready to come to London and bust you up in front of your own fans," Pulev has previously warned.
The Bulgarian, 38, has lost just once in 29 fights. That came in his sole world title fight, against Wladimir Klitschko, in 2013. He has since beaten Derek Chisora and Hughie Fury.
Pulev was first set to challenge Joshua in 2017 but withdrew injured and will now get his opportunity to ruin the champion's hopes of facing Tyson Fury.
There is renewed optimism that a fight for every heavyweight belt can happen, after Fury dethroned Wilder last week.
"Everybody is very clear on this," promoter Eddie Hearn said. "Everybody wants this fight - Anthony Joshua, Tyson Fury, MTK, Top Rank, Frank Warren, Matchroom.
"I promise you this fight will happen. If we have to fight Pulev, we've got to beat Pulev, and if he has to fight Wilder, he's got to beat Wilder again. Both of those things will happen. Fury will beat Wilder again and Joshua will knock Pulev clean out, despite Bob Arum telling us very differently.
"You will get this fight. We will do everything that it takes to make this fight.
"Last time, you had us and Team Wilder and we were locking heads. Right now, you have two guys and two camps that genuinely want this fight, that genuinely will do everything that they can to make this fight. It is the only fight.
"When are we ever going to get the chance of two British world heavyweight champions fighting for the undisputed title against each other? It's never happened before it will never happen again. We'd be clowns, we'd be idiots if we didn't make this fight. We believe we win the fight, they believe they win the fight, so let's see it."
How Fury would approach AJ fight
Would Fury use the same tactics that he utilised to destroy Wilder? The mastermind of that fight, his new trainer Sugarhill Steward, exclusively told Sky Sports how they might prepare to face AJ...
Would Fury use the same game-plan to face Joshua as he did to defeat Deontay Wilder?
Steward told Sky Sports: Probably so. Why do anything different? This is what I believe in wholeheartedly, the Kronk style. So many guys have won with that style. It is a proven method over decades and thousands of successful fights, it isn't just something that has been made up.
We will find out when that fight is made.
Nobody has to believe us. It isn't about talking, it's about actions.
Joshua is far bigger and heavier than Wilder. Would Fury need to use more than just size?
Steward: Definitely. Tyson is intelligent. Now learning something different, he knows what to do.
Describe Joshua as a fighter…
Steward: He is a big, strong, intelligent, talented fighter. Very co-ordinated and strong with great will and determination. He can punch with both hands.
Joshua is one of the other big superstars of boxing but, the only way to truly tell, is for those two guys to fight.