Rory McIlroy said the main sticking points holding up a deal between the PGA Tour and Saudi backers of the rival LIV Golf circuit are the US Department of Justice and conflicting views from players on both sides.
The four-time major champion, who is part of a "transaction committee" engaged in direct negotiations with Saudi Arabia's Public Investment Fund (PIF), said there were different opinions among all the players about the best way forward.
The Northern Irishman also felt the US Justice Department, which previously said it would look into the deal to determine whether it violates antitrust law, was another hurdle that was holding up negotiations.
"Department of Justice. Maybe different interests from the players' side," McIlroy said on Wednesday ahead of the Europe-based DP World Tour's flagship event, the BMW PGA Championship, at Wentworth.
"I'd say maybe half the players on LIV want the deal to get done; half probably don't. I'd say it's probably similar on the PGA Tour.
"Because just like anything, everyone's looking out for themselves and their best interests. You know, it would benefit some people for a deal not to get done, but it would obviously benefit some people for a deal to get done."
LIV Golf, whose mega-money contracts, lucrative purses and no-cut, 54-hole events have managed to lure a number of golf's biggest names, held its inaugural tournament in June 2022.
The PGA Tour, PIF and DP World Tour announced a framework agreement in June 2023 to house all their commercial operations in a for-profit entity.
The framework agreement, perhaps the most unlikely union in professional golf history, stunned the golf world and expired at the end of 2023 but the sides continued to hold talks on how to hammer out the details of a deal.
McIlroy was not present when the two sides met last week in New York to further discuss ways to unify the sport but, despite the hurdles he mentioned, he felt there was also room for optimism.
"To me it seems like the people that are really making the decisions are all rowing in the same direction, which is a really good thing," said McIlroy.
"And even if they are all rowing in the same direction, it still doesn't mean that a deal may get done because it's just a very complicated set of circumstances."