French President Emmanuel Macron told Prime Minister Shinzo Abe that he’s worried about Carlos Ghosn’s conditions in jail, making his strongest comments yet on the fallen car titan and the scandal that has rocked Renault SA’s decades-old alliance with Nissan Motor Co.

“All I’ll say is that I felt the detention was too long and too hard, and I told Abe that,” Macron told reporters in Cairo, referring to a telephone conversation with Abe last Friday. “I’m just concerned that the case of a French citizen should respect basic decency.”

Macron’s views came days after Ghosn stepped down as chairman and chief executive officer of France’s largest carmaker and two months after Nissan booted him out, with the attention shifting to the future of the partnership.

While Renault named Michelin CEO Jean-Dominique Senard as its chairman last week, the French leader has reportedly suggested the executive be made Nissan’s chairman as well to help manage the alliance.

With his public remarks on the case, Macron risks being seen as meddling in Japan’s justice system. Chief Cabinet Secretary Yoshihide Suga said Monday that due process is being followed in Ghosn’s detention and investigation.

“It is being carried out by highly independent investigative authorities, based on appropriate procedures and strict legal judgment, including the orders of the court,” Suga said.

He also said the two carmakers should decide on who becomes Nissan’s chairman, pushing back on the idea of governments getting involved in the talks.

Ghosn has been in custody since his Nov. 19 arrest at Tokyo’s Haneda airport, indicted for allegedly understating his income at Nissan and transferring personal trading losses to the carmaker.

He has been denied bail repeatedly after prosecutors argued he is a flight risk, while his lawyers say he could stay in custody until a trial that may be six months away. Ghosn has denied wrongdoing.

Macron’s involvement in the affairs of the two companies is mainly because of the power the French state wields over Renault. The government owns 15 percent of Renault with extra voting rights, while the latter holds about 43 percent of Nissan with voting rights, giving French leaders an indirect say in decisions that sometimes affect the Japanese carmaker.

Nissan has a 15 percent nonvoting stake in Renault, which also appointed Thierry Bollore as its CEO.

While both companies have repeatedly said they are committed to the partnership, Nissan has long been unhappy about what it considers an outsize French role in the alliance, whose third member is Mitsubishi Motors Corp.

“We will be diligent to ensure the stability of the group,” Macron said.

Renault-Nissan alliance executives will meet this week in Amsterdam, where the company that manages the partnership is based, sources said. The meeting will be the first since Ghosn quit.

Macron has a history with Renault. On Sunday, he defended an increase in the French stake in 2015 on his watch as economy minister. It was a move that had rattled Nissan.

“I was happy I intervened, because I felt that Ghosn had gone too far in the ‘Nipponization’ of the group,” he said.