Beginning this week, drivers will not be able to take older cars into the center of Paris on weekdays.
The ban encompasses most cars made before 1997 and motorcycles made before 2000, and was enacted to combat rampant air pollution in the French capital.
Older cars and motorcycles now face fines for entering the city between 8:00 am and 8:00 pm on weekdays, although they are still free to drive into Paris on weekends.
Announced last year, the ban is one of the toughest measures taken by a European city to curb air pollution so far.
In order to enforce the ban, cars will be required to display colored stickers corresponding to one of six levels of exhaust emissions.
After an initial grace period extending to October, drivers who violate the ban will be fined 35 euros ($39).
The amount of the fine is expected to rise over time, starting with an increase to 68 euros ($75) early next year.
Paris has issued temporary car bans before, but this permanent ban of older cars has incited protests from groups expecting to be impacted by the new policy.
Driver groups initially expressed concern that classic cars—including iconic Citroën 2CVs commonly used to shuttle tourists—would no longer be allowed on Paris streets.
However, the Fédération Française des Véhicules d’Epoque (FFVE) collector-car organization recently met with government officials to secure an exemption for what are deemed “historic vehicles,” according to Hemmings Motor News.
Cars more than 30 years old that display a “Carte Grise de Collection” sticker—as opposed to the “Carte Grise de Normale” sticker issued to normal cars—will be excused from the ban.
FFVE officials reportedly hope to extend the exemption to newer cars that still fall into the “collector” category as well.
Read more: Green Car Reports