Red Bull have sensationally sacked Christian Horner after 20 years as principal of the Formula 1 team.

The decision comes 17 months after he was accused by a female colleague of “inappropriate behaviour” in one of the biggest scandals to engulf the sport.

Horner was twice exonerated of the claims by the Formula One team’s parent company, Red Bull GmbH. He remained in charge of the F1 team throughout the entire process.

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Red Bull did not give a reason for the decision in a statement, but thanked Horner for his work and said he will “forever remain an important part of our team history.”

Laurent Mekies of sister team Racing Bulls will replace Horner.

“We would like to thank Christian Horner for his exceptional work over the last 20 years,” Red Bull managing director Oliver Mintzlaff said in a statement.

“With his tireless commitment, experience, expertise and innovative thinking, he has been instrumental in establishing Red Bull Racing as one of the most successful and attractive teams in Formula 1.

“Thank you for everything, Christian, and you will forever remain an important part of our team history.”

Horner had been Red Bull team principal since it entered F1 as a full constructor in 2005.

But his future has been under the microscope since last year’s scandal at the season-opening Bahran Grand Prix.

Horner was cleared following an internal investigation into claims of wrongdoing by a female staff member at Red Bull, only for hundreds of WhatsApp messages, appearing to be exchanged between Horner and the complainant, were leaked to the F1 world.

Horner, married to former Spice Girls singer Geri Halliwell, fought on and was cleared internally on two occasions, but he lost a number of key figures at Red Bull, with design guru Adrian Newey, chief designer Rob Marshall and sporting director Jonathan Wheatley all departing.

He had performed his team and media duties as normal throughout the British Grand Prix last week.

Horner oversaw eight F1 drivers’ titles — four for Sebastian Vettel and four for Max Verstappen — and six constructors’ titles during his time with the team.

But McLaren has dominated this season in F1, while Red Bull’s performance has dipped, though Verstappen remains third in the standings and the team is fourth.

Verstappen’s future at Red Bull has also been in the spotlight. His father, Jos, claimed in Bahrain a year ago that Red Bull would “explode” if Horner remained in his role.

Verstappen went on to win a fourth consecutive world title last year, but, despite being under contract until 2028, has been linked with a move away.

- With AAP