World No. 1 Rory McIlroy said the feud between the PGA Tour and LIV Golf Series is "out of control" and warned it could leave the sport fractured for a long time.
In an interview with The Guardian, McIlroy described the atmosphere in the game as "us vs. them" and said the escalation of the feud will likely become "irreparable."
The Saudi-backed LIV series has lured away some of the PGA Tour's top members with huge sums of money, while those who joined the rival circuit have been suspended by the U.S.-based organisation.
LIV has filed a lawsuit accusing the PGA Tour of antitrust violations, while the PGA Tour has filed a counterclaim.
"This 'us vs. them' thing has gotten way out of control already," McIlroy said.
"If the two entities keep doubling down in both directions, it is only going to become irreparable. We are going to have a fractured sport for a long time. That is no good for anyone."
Several of McIlroy's former Ryder Cup teammates, including Ian Poulter, Lee Westwood and Sergio Garcia, have joined the circuit, and it is unclear whether they will be allowed to feature in next year's event.
Henrik Stenson has been stripped of Team Europe's captaincy after joining the Saudi-backed series.
"I think it is the first time in my life that I have felt betrayal, in a way," McIlroy added. "You build bonds with these people through Ryder Cups and other things. Them knowing that what they are about to do is going to jeopardise them from being a part of that ever again?
"I would like to think the Ryder Cup means as much to them as it does to me. Maybe it does. But knowing what the consequences could be, I just could never make that decision."
McIlroy said players should have tried to resolve their issues with the established tours rather than switching to LIV.
"I feel like the place where they have been able to build their legacy and build their brand, they have just left behind," he added.
"If people felt so aggrieved about some things, I'd rather be trying to make those changes from inside the walls than trying to go outside and be disruptive."
McIlroy returned to world No. 1 by winning the CJ Cup in South Carolina on Sunday.