Red Bull has pledged not give up on the Formula 1 title fight until it's mathematically impossible for Max Verstappen to win, even after Christian Horner was fired as team principal.

Red Bull sacked Christian Horner, who was Formula One's longest-serving active team principal and one of the most successful of all time, and replaced him on Wednesday with Racing Bulls' Laurent Mekies.

Laurent Mekies, the boss of sister team Racing Bulls, will replace Horner, who has been with the team since its inception in 2005 and led it to 124 wins and numerous championships.