Jockey Frankie Dettori has admitted the drug which led to his six month ban was cocaine.

In an exclusive interview with Channel 4 News just days before his return to riding, Dettori says he is "very ashamed and embarrassed" by the events.

The star rider was suspended for six months by French racing authority France Galop after returning a positive test following a routine examination at Longchamp on September 16 last year.

Dettori is poised to return to action at Leicester on Monday evening.

"I'm very ashamed and embarrassed, and paid a very big price for it, you know. I spent six months not doing the thing that I love, racing," Dettori said.

"Things were going bad. I was depressed and I guess a moment of weakness and I fell for it and I've only got myself to blame. I can't blame anybody else.

"The embarrassment of when it come out, I had to hide in my house for a week. The paparazzi outside.

"The embarrassment of telling the children, you know. You know they still go to school, they might get bullied and so it was a very, very difficult time."

The full interview with Clare Balding will be shown on Thursday (Friday AEST).