A report was published by Sports Business Journal on Wednesday night, citing three people briefed on the resignation as the league seeks a new strategy without Saudi funding.
LIV Golf was planning to announce Thursday a strategy for moving forward without its primary financial backer, including a new board and plans to seek outside financial partners.
LIV Golf did not immediately comment. Any decisions involving Al-Rumayyan would likely come from the PIF, which he has governed since 2015.
Al-Rumayyan signed a framework agreement in 2023 with the PGA Tour and European tour and was set to join the PGA Tour Enterprises board if it was approved.
The deal never materialised, except for ending antitrust lawsuits. PGA Tour Enterprises instead got a minority investment from a consortium of North American sports owners.
Scott O'Neil, who replaced Greg Norman last year as CEO of LIV Golf, had told London-based TNT two weeks ago during LIV's Mexico City event Saudi funding was good through the 2026 season and he would "work like crazy" to create a solid business plan.
With financial muscle from Saudi Arabia's sovereign wealth fund, LIV was able to spend $1 billion to land the likes of Bryson DeChambeau, Brooks Koepka, Phil Mickelson, Australian Cameron Smith and eventually Jon Rahm, the last big signing at the end of 2023.
The newsletter Money in Sport reported earlier this year LIV Golf already had spent $5 billion since the league launched in 2022, a figure that would be $6 billion by the end of this year.
LIV Golf earlier this week said they were postponing their June 25-28 event in Louisiana to the autumn. The next event is scheduled for May 7-10 in northern Virginia, and O'Neil had said in a memo to staff two weeks ago the season would be uninterrupted and "full throttle."
But the league that now offers $30 million in prize money at each event already is trying to chart a course for staying solvent after this year.
LIV plans to announce a new board and share plans to reposition the league for 2027 and beyond, though that likely would be with fewer than the 14 events on this year's schedule. It also plans to lean into the concept of team franchises.
Al-Rumayyan was all about team golf when he and Norman launched the league, even though the team concept was one reason it took more than three years for LIV to get recognised by the Official World Golf Ranking.