Should McLaren not have a race-seat open for Kevin Magnussen, Eric Boullier says he will "never stop" the Dane from signing with a rival outfit.
Having been demoted to a reserve driver role this season, Magnussen is determined to return to racing in 2016.
The 22-year-old has been linked to newcomers Haas F1 while America's IndyCar series is another option.
Should either of those come to fruition, Boullier says McLaren will not stand in their driver's way.
"If we can offer him something here, a drive – and I'm not the only one to decide – yes, he obviously takes priority," the Racing Director told Autosport.
"He is a McLaren driver, and he is always claiming he would like to race again for McLaren.
"But if we cannot then personally I would never stop him from racing somewhere else, of course."