Carlos Ghosn is facing new charges he improperly received $9 million ($A12.5m) in compensation after brokering the deal to create a joint venture between Nissan and Mitsubishi Motors, the Japanese car-makers announced on Friday.
The new embezzlement claims add to a growing list of charges against the ousted chairman and could see Ghosn spend decades behind bars if proven.
The latest claims suggest that, following an investigation by both car-makers, the man once regarded as the saviour of Nissan was paid by the Netherlands-based joint venture without consulting two other board members, Nissan chief exec Hiroto Saikawa and Mitsubishi boss Osama Masuko.
Releasing a statement, the car-makers said: "Nissan views the payments Ghosn received from [the joint venture company] to be the result of misconduct and will consider measures to recover from Ghosn the full sum".
Ghosn, who has been detained since his arrest in November by Japanese investigators, is believed to have denied the new charges against him.
The length of his detention, without trial, has drawn criticism throughout the car industry and raised a growing suspicion ousted Ghosn was in embroiled in a Game of Thrones-style power play.
Fuelling these rumours is the fact that, despite his arrest and charges levelled against him, Ghosn remains the chairman and chief executive of Renault; although a meeting in the next few days could yet see him replaced.
The timing of Ghosn's arrest was just days before the French-Lebanese-Brazilian had scheduled a meeting to formalise Nissan's absorption as part of Renault, instead of its current position as an alliance partner.
The Renault-Nissan-Mitsubishi alliance was the world’s biggest car-maker in 2017 and it will almost certainly retain that title for 2018, shifting more than 10 million cars a year.