Tokyo, Jan 14 (IANS): The wife of ousted Nissan Motor Chairman Carlos Ghosn has urged immediate action against the "harsh treatment" meted out to him in a Japanese jail, where he has been detained for nearly two months for alleged financial misconduct.

In a letter to the Human Rights Watch (HRW), Carole Ghosn described constant interrogations and appealed for action, the BBC reported on Monday.

"For hours each day, the prosecutors interrogate him, browbeat him, lecture him and berate him, outside the presence of his attorneys, in an effort to extract a confession," Carole Ghosn said in her nine-page letter to the advocacy group.

There has been no immediate reaction to the claims from Japanese prosecutors.

Carlos Ghosn, a towering figure of the car industry, faces three charges of financial misconduct including understating his income and aggravated breach of trust.

He has denied any wrongdoing.

In the letter, Carole Ghosn said he was being held in a small, unheated cell and denied daily medications.

He has lost weight since his detainment, she said, and eats mainly rice and barley.

"I urge Human Rights Watch to highlight his case... to press the government to reform its draconian system of pretrial detention and interrogation," the letter said.

Ghosn's lawyers said he could be in jail for another six months before his first trial is held, the BBC said.

"No one should be forced to endure what my husband faces every day, particularly in a developed nation like Japan, the third largest economy in the world," the letter said.