French carmaker Renault is to recall more than 15,000 vehicles to undergo engine modifications to comply with emission standards.

The announcement was made by French Ecology Minister Segolene Royal, whose portfolio includes transport.

In a radio interview she said that Renault “has committed to recalling a certain number of vehicles, 15,000 vehicles, to check them and adjust them correctly so that the filtration system works” in all temperatures”.

Government fraud inspectors visited three Renault sites last week and carried out a number of tests on vehicles before announcing that no pollution cheating software had been found on Renault cars.

However a French government-appointed commission said the company’s diesel cars had failed pollution tests.

Fraud investigators inspect three Renault factories to check vehicle emissions technology https://t.co/NSm0cgh4v8pic.twitter.com/7l1VXDCv3p — BBC News (World) (@BBCWorld) January 14, 2016

As news filtered through to the markets that officials were checking on Renault the car manufacturer saw is shares fall by ten percent last week losing the company billions. They remained down on Monday but picked up on Tuesday.Segolene Royal said that Renault is not alone in exceeding emissions targets and other carmakers will be questioned by the government.

Several hours after Royal spoke Renault’s Chief Competitive Officer Thierry Bollore said the carmaker will announce measures in March to reduce real world emissions of nitrogen oxide (NOx) pollutants from its latest diesel vehicles

In a briefing for reporters at the company’s headquarters west of Paris he explained that engine adjustments, to be delivered in the form of a software upgrade, will be available for vehicles with the latest Euro 6 generation of diesel engines.

Starting in July, voluntary engine checks will be offered to owners of about 700,000 vehicles that may be eligible for the upgrade, Bollore said.

Renault is France’s second biggest car manufacturer and the French state owns nearly 20 percent of the company.