Drug use to cost top driver his career?

The 36-year-old said: "Auto sport is maybe over for me."

Montagny’s raced seven times for the now-defunct Super Aguri F1 team in 2006. He told French sports daily L'Equipe he was driving for the Andretti Autosport Formula E team and tested positive at the Malaysian round of the series in Putrajaya November 22.

'I WAS ASHAMED'

He missed the subsequent race in Punta del Este, Uruguay, and told his followers on Twitter at the time that his absence was due to health reasons.

He did not contest the test result and is now awaiting a sanction from the governing International Automobile Federation.

"I knew, in my head, immediately. I knew it was over,” he told the newspaper. “I got on the plane... then I called my parents, to explain. I was ashamed.

“I made a stupid mistake, I am guilty."