Nissan ex-boss Carlos Ghosn has accused former executives at the firm of “backstabbing” and says he is innocent of all charges against him.
In a pre-recorded video released by his legal team, he said he was victim of a “conspiracy” and wanted a fair trial.
Nissan said in response that there was “substantial evidence” against him.
Mr Ghosn was arrested for a fourth time last week while on bail awaiting trial on charges of financial misconduct and breach of trust.
“Aside from any criminal matters, Nissan’s internal investigation has uncovered substantial evidence of blatantly unethical conduct,” the company said.
“Further discoveries related to [Mr] Ghosn’s misconduct continue to emerge.”
In the video message, the 65-year-old, who was first arrested in November, maintained his denial of any wrongdoing or misconduct.
“This is about a plot, this is about conspiracy, this is about backstabbing – that’s what we are talking about,” Mr Ghosn said in the video, released at a news conference.
“There was a fear that the next step of the alliance… would in a certain way threaten some people or eventually threaten the autonomy of Nissan.”
Mr Ghosn was the architect of the alliance between Nissan and French carmaker Renault, and brought Mitsubishi on board in 2016.
The fall from grace for the industry titan has attracted global attention. It has also put a spotlight on fighting within the carmaker alliance and on Japan’s legal system.
His wife Carole Ghosn has flown to France to ask the government there to intervene on her husband’s behalf.
What has happened so far?
Prosecutors said Mr Ghosn’s latest arrest related to transfers of Nissan funds totalling $15m (£11.5m) between 2015 and 2018.
They allege that $5m of that amount was used by Mr Ghosn for personal expenditure.
Local media had previously said that authorities had been building a new case against him involving payments to a dealership in Oman.
He had been released on bail in March after being in prison for more than three months.
Mr Ghosn was first detained in November, charged with under-reporting his pay package for the five years to 2015.
In January, a fresh charge claimed he understated his compensation for another three years. He was also indicted on a new, more serious charge of breach of trust.
He is credited with turning around the fortunes of Nissan and Renault over several years.