Macron said he had discussed with Japanese Prime Minister Shinzo Abe the situation surrounding the arrest of Franco-Brazilian-Lebanese executive, Carlos Ghosn.
President Emmanuel Macron said on Sunday that France wants to maintain a "balance" in the alliance between automakers Renault and Nissan following the arrest in Japan of Carlos Ghosn.
"We are being vigilant to ensure the balances of the alliance are preserved," Macron said at a news conference on the first day of a visit to Egypt.
"I don't believe at all that what is happening, which is an individual case, is likely to reverse the balance of the alliance," which had shown "stability," the French president added.
Renault currently owns 43 percent of Japanese automaker Nissan, which itself has a 15 percent stake in the French company and 34 percent of Mitsubishi Motors.
An overhaul of the group following the arrest in November of its chief executive Ghosn in Japan, on charges of under-reporting his income, could harm Renault's influence.
Macron said he had discussed with Japanese Prime Minister Shinzo Abe the situation surrounding the arrest of the Franco-Brazilian-Lebanese executive.
"I was simply concerned that the fate of a French compatriot respects the minimum decency that we are entitled to expect," he said.
Macron said he had told Abe on several occasions that he thought Ghosn's time in detention was "very long" and described the conditions he was being held in as "harsh".
Speaking Monday morning in Tokyo, Japanese government spokesman Yoshihide Suga defended the country's judicial system, while declining to elaborate on the conversation between Abe and Macron.
"I'd like to refrain from disclosing details of exchanges between the two leaders," he told reporters.
"But, I understand that investigations into criminal cases are conducted by a highly independent investigation agency through appropriate procedures based on strict judicial judgements such as court orders," he said.
He added that Abe had said Japan wants to see the alliance between Nissan and Renault "maintained and enhanced".
Ghosn's shock November 19 arrest exposed tensions in the alliance that groups Renault, Nissan and Mitsubishi Motors.
While the two Japanese firms swiftly replaced Ghosn, Renault waited until last week to appoint two experienced auto executives to replace the 64-year-old: Thierry Bollore as chief executive and Jean-Dominique Senard as chairman.