Red Bull boss Christian Horner has ruled out a move for Sebastian Vettel's services as Max Verstappen's teammate in 2021 as the team does not want "two alpha males".
Vettel and Ferrari could not reach an agreement on an extension to Vettel's current contract, which expires at the end of this year. Ferrari has already signed Carlos Sainz as his replacement for next year.
Vettel's next move is unclear, although his options for a top drive are limited. He won his four world championships at Red Bull at the start of the 2010s, but Horner has played down the prospect of a reunion.
"I think it's enormously unlikely," Horner said on Sky Sports News. "We have a long-term agreement with Max. Alex [Albon] is doing a good job. We've got a good dynamic within the team.
"Experience shows that two alpha males, it doesn't tend to pan out well. Sebastian is still a very competitive grand prix driver. I don't think it would be conducive for our team to have two alphas.
"We're happy with the driver line-up we have. I'm sure he's not short of options moving forward, but he's chosen that it hasn't worked out for him at Ferrari."
Vettel's chances of a Mercedes seat also look slim. Mercedes boss Toto Wolff is in talks with Lewis Hamilton about renewing the reigning world champion's contract beyond this season. It seems likely the team will either retain the services of Valtteri Bottas for 2021 or promote junior driver George Russell from Williams to partner Hamilton.