A “deeply ashamed” British champion rider has withdrawn from the Paris Olympics after the emergence of a shocking video.

Charlotte Dujardin, who is Britain’s joint-most decorated female Olympian, is being investigated by equestrian’s governing body amid allegations she mistreated a horse.

“A video has emerged from four years ago which shows me making an error of judgment during a coaching session,” Dujardin said on Wednesday (AEST).

“Understandably, the International Federation for Equestrian Sports (FEI) is investigating and I have made the decision to withdraw from all competition – including the Paris Olympics – while this process takes place.

The six-time dressage medallist did not elaborate on the investigation. However, there are multiple reports of allegations she whipped a horse “24 times … like an elephant in a circus”.

“She took the long whip and she was beating the horse more than 24 times in one minute, and really hard, really harsh, really tough. It was like an elephant in the circus,” Dutch lawyer Stephan Wensing, who represents the 19-year-old who lodged the formal complaint,  told Britain’s Telegraph newspaper.

“At that time, my client was thinking this must be normal – ‘She is an Olympic winner. Who am I to doubt?’ … But last year my client saw others suspended in the UK and elsewhere.”

“She eventually made a decision to let me admit the complaint to the FEI, who took this immediately very seriously.”

 

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Dujardin has been provisionally suspended for six months while the FEI investigates. Wensing said he was pleased the FEI had taken such a strong stand.

The champion rider also apologised in a statement to social media.

“What happened was completely out of character and does not reflect how I train my horses or coach my pupils. However, there is no excuse. I am deeply ashamed and should have set a better example in that moment,” she said.

Dujardin said she was “sincerely sorry” for her actions and was “devastated” about letting down the team, fans and sponsors.

“I will co-operate fully with the FEI, British Equestrian Federation and British Dressage during their investigations, and will not be commenting further until the process is complete,” she said.

Dujardin won three golds, a silver and two bronze medals at the London, Rio and Tokyo Games.

Her six medals make her Britain’s joint-most decorated female Olympian alongside cyclist Laura Kenny.

Dujardin was due to compete in both the individual dressage and the team event in Paris alongside Carl Hester and world champion Lottie Fry.

-with AAP