Promoter Eddie Hearn says there is "absolutely no question" Anthony Joshua will face Deontay Wilder in a heavyweight unification bout in 2018.
Wilder called out Britain's IBF and WBA champion after defending his WBC title against Bermane Stiverne on Saturday.
Hearn met Wilder's promoter in the USA on Thursday and urged the American to keep his financial demands realistic.
"We need a middle ground between reality and fantasy," said Hearn. "If we can, I don't see problems making the fight."
He added: "Unfortunately, Anthony has to overpay opponents. If we offered Deontay the correct purse for this fight it would never happen because he would think it was disrespectful.
"So we have to overpay him to make it happen. And we have to give him respect because he's a great fighter, a great champion, really exciting, a great self-promoter.
"I feel a bit bad for him, he's got no promoter pushing him."
Speaking to IFL TV, Hearn pointed to what he perceives as Wilder's limited profile in the United States by asking people on a New York street if they recognised the 32-year-old's name.
Hearn emerged from his meeting with Wilder's team on Thursday stating there was a "desire" from both camps to "make this happen".
He was unable to clarify if it would be Joshua's next fight or if a summer bout is more likely but stressed a meeting between the two unbeaten fighters would be the "biggest fight in world boxing", adding: "Joshua wants this fight bad, Wilder wants it bad as well."
Hearn added: "It's going to happen in 2018, absolutely no question. You can't get away with not making fights any more because when you do you wake up to a million tweets."
Joshua, whose past two bouts have been in front of about 90,000 fans at Wembley Stadium and over 70,000 at Wales' Principality Stadium, is keen to keep fighting in the UK.
Fighting overseas has been mooted by the 28-year-old's management but Hearn concedes any move to Las Vegas to face Wilder would result in higher-priced tickets because the venues in the American city are substantially smaller than UK options.
Should the fight take place next, the winner would hold three of the four major titles in the heavyweight division, with New Zealand's Joseph Parker in possession of the WBO belt.