The mayor of Paris, Anne Hidalgo, has introduced a ban on through traffic from the historic city centre to cut pollution and congestion.
The French capital's police chief said the new rules will be enforced with a light touch, but cars and other motorised vehicles can no longer go into the city's first, second, third and fourth districts – or arrondissements – unless they have business there.
The new ban covers an area of 5.5 square kilometres that includes the Louvre Museum, the Place Vendome, the Tuileries Garden and the Marais neighbourhood, as well as many cultural venues and shopping areas.
Ms Hidalgo has long sought to limit car traffic in favour of less polluting means of transport, notably bicycles. Over the past decade, Paris has turned several areas previously dominated by cars over to cyclists and pedestrians, including stretches of the banks of the river Seine.
Much of the busy Place de la Concorde is set to be next, and the Pont d'Iéna bridge near the Eiffel Tower has not reopened to traffic since the Olympics. Ms Hidalgo promised the transit ban during her 2020 re-election campaign for mayor, but its implementation was postponed several times.
Other European cities including Rome, Milan and Madrid have taken similar measures. The Paris mayor's office said its own traffic limitation scheme was "one of the most ambitious" on the continent.
The new through-traffic rules require drivers to carry proof that they have a reason for being there and are not just "using the centre of Paris as a shortcut", said Ariel Weil, mayor of central Paris. People who live or work in the area have free access, as do buses, taxis, emergency services and disabled drivers.
Anyone else who can show that they are "stopping there" for a doctor's visit or to make a delivery can pass, too. Going to the cinema or the theatre are also acceptable reasons to drive into the area. Paris officials have said there will be no fines for the first six months to allow drivers to get accustomed to the new rules.
Paris police chief Laurent Nunez, who rarely sees eye to eye with city hall on the question of car traffic, promised to ensure that there would be "as few constraints as possible" for motorists. He told Le Parisien newspaper that measures such as online registration, which was used to enforce traffic restrictions during the Paris Olympics this summer, "is not what I favour".
Deputy mayor for transport David Belliard, a member of France's Green Party, said the city is still working out how exactly the new rules would be enforced, and would establish a list of accepted documents in collaboration with police. Motorists themselves appeared unsure about the new rules.
"We're not happy with this ban," said the driver of a delivery van stopped by a police officer on Monday before being told that he could pass as "you're working", as she handed him an explanatory leaflet. "I hope my residential parking sticker will be enough," said a psychologist who rides her scooter through the zone each day.
Officials say they expect a noticeable improvement in terms of air and noise pollution from the measure, especially for the 110,000 residents of the four districts. Major thoroughfares such as the Avenue de l'Opera, which runs from the old opera house to the Palais Royal, could have their car traffic cut by a third.
Critics say the new rules will simply shift transit traffic to adjacent neighbourhoods such as the city's Left Bank, which is not covered by the ban. "It's going to be an almighty mess," said Aurelien Veron, spokesman for the Changer Paris (Change Paris) opposition group in the Paris municipal council.
But officials said projections showed that any additional traffic in neighbouring areas would be "extremely limited". Some shop owners, meanwhile, said they feared that traffic restrictions could hurt business.
"If city hall wants to kill local shops this is the way to do it," said Patrick Aboukrat, regional president of France's national clothes manufacturing association. He told the Echommerces trade magazine that shop owners would challenge the new transit rules in court.
