Arrested auto executive Carlos Ghosn improperly received €7.8m in compensation from a joint venture between Nissan and Mitsubishi Motors, the companies said today. 

A joint investigation found that Ghosn, ousted as chairman from both automakers, was compensated by the Netherlands-based joint venture without any discussion with two other board members, Nissan CEO Hiroto Saikawa and Mitsubishi CEO Osamu Masuko. 

Nissan holds a controlling stake in Mitsubishi Motors. 

Ghosn, arrested and detained in Tokyo since November 19, has been indicted in Japan on charges of under-reporting his salary for eight years up to March 2018, and temporarily transferring personal investment losses to Nissan during the global financial crisis. 

Ghosn has denied the charges against him. 

Reuters reported earlier this week about the alleged improper compensation to Ghosn by the joint venture and that Nissan was considering filing for damages, citing a source. 

Nissan said today that it would consider ways to recover the full amount from Ghosn, and Mitsubishi said it would consider ways to hold him responsible. 

The latest allegations are likely to add pressure on the Japanese automakers' partner Renault to cut ties with Ghosn.

Unlike Mitsubishi and Nissan, Renault has kept Ghosn as CEO and chairman, but its biggest shareholder, the French government, has been urging it to replace him.

The French automaker holds around 43% of Nissan, the biggest partner in the alliance by sales and which in turn holds a non-voting 15% stake in Renault. 

Mitsubishi became the smallest member of the three-way automaking alliance when Nissan in 2016 took a 34% stake in the company.