Lando Norris says he is prepared to leave McLaren if the British team has no place for him within a year or so.
This year, McLaren will line up with an unchanged driver pairing of Fernando Alonso alongside Stoffel Vandoorne.
But youngster Norris, the new reigning F3 champion, steps up into the reserve role for 2018.
About his future, he said: "You could say it depends on what he (Alonso) does.
"So we’ll have to wait to see what Fernando wants to do because I think they (McLaren) are also happy with Vandoorne," Norris, 18, is quoted by Marca sports newspaper.
The young Briton will combine his McLaren role with Formula 2 this year.
"I can develop a lot and definitely improve as a driver in 2018," Norris said.
"Obviously my goal is to be at McLaren but if I cannot get a place here, then I’ll have to look for other opportunities.
"If they tell me there will be no place for three years then it’s obvious that I’ll have to go somewhere else, but if it’s only a year, I think I’ll continue with McLaren," he added.