McIlroy needs to play four European Tour tournaments outside of the majors and World Golf Championship events, but only has two on his schedule.
Players must be a member of the European Tour to be eligible to play in the Ryder Cup and, under new regulations introduced in January, 2017, “players cannot be a European Ryder Cup captain or a vice-captain if they decline membership of the European Tour or fail to fulfil their minimum event obligation in any season, from 2018 onwards.”
McIlroy said ahead of the season-ending DP World Tour Championship in Dubai: “I am starting my year off in the States and that will be the big focus of mine up until the end of August and then we will assess from there.”
“I guess my thing is that I want to play against the strongest fields week-in and week-out and for the most part of the season that is in America. If I want to continue to contend in the majors and to continue my journey back towards the top of the game, then that’s what I want to do.
“Right now that is all sort of up in the air, but if it were to be that I don’t fulfil my membership next year, it’s not a Ryder Cup year so it’s not the end of the world.
“I am always going to want to play the Ryder Cup, so if that does happen so be it and I will try and make the Ryder Cup team the year after.”
McIlroy’s decision will be a major blow to European Tour chief executive Keith Pelley, who launched the Rolex Series last year in an effort to prevent Europe’s star names from flocking to the lucrative PGA Tour.
The eight events each have a prize fund of at least £5.4m, with the BMW PGA Championship moving to September and the Italian Open to October following the US PGA Championship decision to switch from August to May.
Leeds’ Daniel Gavins carded a two-under-par 69 to maintain his position at the top of the leaderboard as the 156-player field was reduced to 77 following the fourth round of European Tour Qualifying School Final Stage.
With 36 holes to go in Tarragona, Spain, Gavins holds a one-shot lead over France’s Clément Sordet.
Gavins said: “I’ve come through Q-School before and I know I can do it again. There’s still a long way to go so I just need to take it one shot at a time.”
A 69 kept Huddersfield’s Chris Hanson in the top 25 that retain playing privileges after the six rounds, but Rotherham’s Jonathan Thomson and Leeds’ Nick McCarthy are four shots off the mark with Hallamshire’s Joe Dean a further stroke back.
Yorkshiremen Simon Dyson, Richard Finch, John Parry and amateur Ben Hutchinson all missed the cut ending their hopes of playing on the European Tour next season.