Addressing lawmakers at the National Assembly, Eckert said government legal services were preparing action to recover “lost tax receipts” from carmakers whose vehicles should have incurred higher green penalties at the time of sale.

The diesel scandal, which broke a year ago when Volkswagen admitted cheating U.S. nitrogen oxide (NOx) emissions tests, prompted industry-wide investigations in France and other countries.

Besides on-the-road NOx emissions far in excess of regulatory lab scores, the inquiries found gaps between claimed CO2 output and actual fuel efficiency for many car models.

Under France’s “bonus-malus” scheme, cars with lower CO2 emissions and fuel consumption benefit from sales subsidies funded by penalties on the sale of less economical vehicles, based on the amount CO2 emitted per kilometer.

“There will be no leniency nor particular severity,” Eckert said on Wednesday. The budget minister also announced plans to shift green incentives from hybrids to pure-electric cars and begin phasing out fuel tax advantages for diesel-powered fleets.