F1 engine rules

Red Bull team principal Christian Horner doubts Formula 1 will be able to introduce a new set of engine regulations until 2023 at the earliest despite long-held plans to make changes two years earlier.

Red Bull team boss Christian Horner is "very encouraged" by Formula 1's early engine plans for the 2021 season as the sport's bosses look to increase the sound of the power units while making them more affordable.