Red Bull could choose to release Pierre Gasly from his contract with the team if an opportunity to race elsewhere in Formula 1 arises, after the team awarded Daniil Kvyat a new contract alongside Carlos Sainz at Toro Rosso for 2017.
Gasly, who is on the brink of securing the GP2 title, looked the most likely candidate to secure the second Toro Rosso seat alongside Sainz, having conducted tyre testing for Red Bull recently.
Kvyat meanwhile was demoted from Red Bull to Toro Rosso in favour of Max Verstappen.
Christian Horner however says it would be unfair not to give the Russian a second chance given his age and recent form and suggested Gasly would have to wait or find a seat elsewhere.
"Daniil Kvyat is a good young driver and he's had a tough time this year," Horner told Sky Sports F1. "Mentally that's been tough for him. He's addressing some of the issues that he had a problem with earlier in the year and he's finding his confidence again.
"At 21 years of age, we felt it right to give him another opportunity in the Toro Rosso against Carlos Sainz. I think he'll benefit from that.," he added.
"The clear facts are that we felt it better to give Daniil a seat that award it to Pierre at this time, who we still rate highly. He's an important part of the team, conducting important tests and development work for us. but there's only so many cockpits for our drivers.
"It's a possibilty if the right opportunity came up for him we'd consider releasing him for that if he can dovetail it with some of the work he's doing for us."
