Alternate driving days are being introduced in the French capital, Paris, in an attempt to tackle dangerous levels of air pollution.
Under the scheme, cars will be allowed on the roads on alternate days according to whether their numberplate is odd or even, the BBC reports.
It's the first such ban for 20 years, as politicians try to get rid of health-threatening smog days before municipal elections.
Free public transport, including bicycle and electric car sharing schemes, was introduced last week as a visible haze hung over Paris streets.
The French government made the decision after air pollution exceeded safe levels for five days running in Paris and surrounding areas.
Motorcycles will also be covered by the ban.
The smoggy conditions have been caused by a combination of cold nights and warm days, which have prevented pollution from dispersing.
The capital's air quality has been one of the worst on record, French environmental agencies say, rivalling the Chinese capital, Beijing, one of the world's most polluted cities.
On Friday, pollution levels hit 180 microgrammes of PM10 particulates per cubic metre, more than double the safe limit of 80.
PM10 particulates are emitted by vehicles, heating systems and heavy industry.