BRUSSELS/PARIS -- France will seek more information from criminal investigations into Renault and Volkswagen diesel emissions before deciding whether to ban any of their cars from sale, Environment Minister Segolene Royal said on Thursday.
Speaking to European parliamentarians in Strasbourg, the French minister also said an examination of Renault engine software was underway, with initial findings due next month.
"We will be asking the consumer fraud investigators and prosecutors to communicate any findings that will enable us to establish whether it's necessary to withdraw sales authorizations," Royal said.
Following VW's exposure for using software to cheat U.S. tests, Renault and others have attracted scrutiny for their own use of "defeat devices" that reduce the effectiveness of technology to filter toxic nitrogen oxides (NOx) from exhaust gases.
A Renault spokesman declined to comment.
VW and Renault face French criminal probes based on suspicions outlined to prosecutors by the DGCCRF consumer fraud agency that they had broken emissions laws.
Public energy research agency IFPEN is still examining Renault engine software, Royal said. "It's underway and will be published. We'll have the first results in December."
Many carmakers including Renault, Opel and Fiat use engine software to reduce the effectiveness of their anti-NOx technology outside certain conditions and temperature ranges.
Expert opinions differ as to whether such software is legal under EU law, which allows defeat devices when deemed necessary to protect the engine.
Some national authorities including Germany have said the law is too vague to allow proper policing of defeat devices, but Royal called EU law "perfectly clear."
Royal said the French criminal probe is also looking into separate concerns over Renault's Captur SUV, when asked about reports that some investigators believed its test findings indicated another type of defeat device.
"The consumer fraud directorate has alerted the prosecutor," Royal said. "So clearly we have taken action over this observation."