Red Bull Formula One chief Christian Horner is under investigation by his team after an accusation of “inappropriate behaviour”.
It is understood the allegation has been made by another member of staff for the British-based team, the PA news agency reported.
The 50-year-old, who is married to former Spice Girls singer Geri Halliwell and has been Red Bull Racing team principal since 2005, strongly refutes the accusation.
Horner said: “I completely deny these claims.”
A spokesperson for Red Bull – the Austrian energy drinks company which owns the F1 team – told PA: “After being made aware of certain recent allegations, the company launched an independent investigation.
“This process, which is already under way, is being carried out by an external specialist barrister.
“The company takes these matters extremely seriously and the investigation will be completed as soon as practically possible. It would not be appropriate to comment further at this time.”
Horner has been team principal at Red Bull since their entry into F1 some 19 years ago, overseeing seven drivers’ world championships and six constructors’ titles.
Last season, one of the team’s two drivers, Max Verstappen, won his third consecutive world championship.
Red Bull won 21 of the 22 rounds staged last year, with Verstappen setting a record of 10 consecutive race victories.
Horner was awarded a CBE for his services to motorsport in the New Year Honours List.
Red Bull are due to launch their latest car on 15 February ahead of the new season, which starts in Bahrain on 2 March.