Former Nissan executive Greg Kelly reportedly has pleaded not guilty to charges he helped former company chief Carlos Ghosn under report income as his trial began in Tokyo on Tuesday (15 September).

"I deny the allegations. I was not involved in a criminal conspiracy," Kelly told the court, according to a court pool report cited by the Reuters news agency.

A representative from Nissan, which is also standing trial, said the automaker did not contest the charges.

Nissan Motor last June strongly refuted media suggestions of a conspiracy within the automaker to oust former chairman Carlos Ghosn.

Reuters noted at the time the 2018 arrest of Ghosn in Japan on financial misconduct charges had led to much speculation that the move was orchestrated by Nissan executives who opposed closer ties with Alliance partner Renault.

"I know that in books and the media there has been talk about a conspiracy but there are no facts whatsoever to support this," Motoo Nagai, chairman of Nissan's auditing committee, told shareholders at the company's annual general meeting in Japan.