Christian Horner has ruled out the prospect of Sebastian Vettel returning to Red Bull next season. 

Vettel is in his final year with Ferrari and revealed on Thursday he would be open to a second spell with Red Bull. 

The German driver won all four of his Formula One world titles during his previous stint with the team before joining the Scuderia in 2015. 

However, team principal Horner insists there is no seat for the 33-year-old to fill, as Red Bull are happy with current duo Max Verstappen and Alex Albon.  

"The topic [of Vettel rejoining Red Bull] has been discussed," he told Sky Sports F1. "We had a brilliant time with Seb and he will forever be a part of our history. 

"We didn't expect him to be on the market this year, and our commitment is to our existing drivers. We think we've got a great pairing in Max and Alex, and think that has great potential for the future as well. 

"Unfortunately, it's not something we are going to be able to accommodate. 

"I guess he's got a couple of choices available to him, I assume Racing Point, or a year out and re-evaluate the options in a year's time." 

Vettel said he held talks with Renault before Fernando Alonso's return was confirmed.