The woman in the Christian Horner controversy has lodged an official complaint about his behaviour with Formula 1’s governing body, the FIA.

BBC Sport has learned the complainant, who accused Red Bull’s team principal of inappropriate behaviour, has registered a grievance with the FIA’s ethics committee.

Horner, 50, has always denied the accusations made against him.

The woman’s actions follow two previous whistleblower complaints registered with the FIA in the past few weeks.

BBC Sport has learned that one was made to the FIA ethics and compliance hotline on 2 February, and made direct reference to Horner’s behaviour towards a female employee, asked the FIA to look into it, and expressed a fear that Red Bull could try to cover it up.

The second complaint on 6 March referenced the first and warned that the whistleblower would next inform the media.

In a statement, the FIA said: “Enquiries and complaints are received and managed by the compliance officer, and the ethics committee where appropriate.

“Both bodies operate autonomously, guaranteeing strict confidentiality throughout the process.

“As a consequence, and in general, we are unable to confirm the receipt of any specific complaint and it is unlikely that we will be able to provide further comment on the complaints that we may receive from any parties.”

A Red Bull Racing spokesperson said it was not aware of the complaint and did not want to comment further.

The official complaint made by the woman to the FIA follows her decision to appeal against Red Bull’s dismissal of her complaint.

Red Bull’s decision was made after an investigation conducted by a lawyer.

Last week, Red Bull suspended her from her role with the team.

The accusations against Horner came to light in early February, but the investigation into his behaviour had started almost a month before. It lasted 10 weeks, according to Red Bull.

Red Bull appointed an external lawyer to investigate the claims. After his report was submitted to the company’s board, it decided to dismiss the complaint.

The following day, a cache of messages purporting to involve Horner was leaked to nearly 150 senior F1 insiders and media.

Horner has said it is “time to draw a line under” the controversy.

Red Bull has refused to give further details of the case, citing confidentiality.

BBC Sport has previously reported that the reason given by Red Bull to the employee was that she had been dishonest.

Horner said at last weekend’s Saudi Arabian Grand Prix: “The reality is that there was a grievance raised, it was dealt with in the most professional manner by the group, that appointed an independent KC, one of the most reputable in the land.

“He took time to investigate all the facts. He looked at everything and he came to a conclusion where he dismissed the grievance.

“As far as I’m concerned, as far as Red Bull is concerned, we move on.”

The controversy is at the centre of a power struggle inside Red Bull, involving Horner, the motorsport adviser Helmut Marko, the team’s three-time world champion Max Verstappen and his father Jos, Verstappen’s manager Raymond Vermeulen and the two owners of the company.

Last weekend, an intervention by Max Verstappen was instrumental in keeping Marko from being dismissed.

Chalerm Yoovidhya, the 51% shareholder, has backed Horner and forced 49% shareholders Red Bull Gmbh in Austria to back down in wanting to force him out.