Fernando Alonso's shock decision to tackle this year's Indy 500 could entice McLaren to contest the race or other Indycar events with a full works effort in the future.
Alonso will miss this year's Monaco Grand Prix which conflicts with the Indy 500 and make his debut in a McLaren-entered Andretti-Autosport car.
The event could wet McLaren's appetite for a series which has always been part of the Woking-based outfit's heritage, with McLaren cars winning at the Brickyard three times in the 1970s, and twice with factory driver Johnny Rutherford.
"I've attended the Indy 500, and I came away hugely impressed by the scope and scale of this enormous and well-organised event, and the sheer enthusiasm of the hundreds of thousands of fans in attendance," said McLaren shareholder and MTG executive committee principal Mansour Ojjeh.
"More than 40 years [after McLaren's Indy 500 wins], I'm pleased and proud that we're about to embark on a new IndyCar era for McLaren, this time with Andretti Autosport and Honda.
"The Indy 500 is the only IndyCar race we'll be entering this year, but we may possibly repeat that in years to come.
"And it's just possible that we may even run a full-works McLaren IndyCar operation at some point in the future. We'll see."
While on the subject of diversification, Manour Ojjeh also alluded to a possible return of McLaren to Le Mans.
"Equally, we may potentially enter the Le Mans 24 Hours again some time. We won it outright in 1995 with our iconic McLaren F1 GTR - but to be clear we have absolutely no definite plans to do so at this stage."