Paris and several major cities suffering from worsening pollution are risking the wrath of motorists to give citizens a breath of fresh air.

The government wants the operation dubbed "Downtown, without my car" to turn into an annual event and trigger a public debate in this car-mad country on how to rid cities of traffic jams and exhaust fumes.

"For decades, cities have been built for cars...we can't let things get out of control when we are close to asphyxia," transport minister Jean-Claude Gayssot told the daily Le Monde.

Motorbikes, emergency services, doctors, taxis and electricity-powered cars will be exempt from the ban. Motorists are being encouraged to use public transport, and authorities in some towns will provide bicycles free of charge.

Rouen, Nantes, Tours, Strasbourg andGrenoble are taking part. But some of the biggest cities, like Lyon and Marseille, have declined.

In most cities, the ban is far from extensive. After much negotiation, the Paris city hall agreed to close down only 57 km (35 miles) to vehicles, out of a total 1,600 km (1,000 miles), from 7 A.M. to 9 P.M.

The car-free areas will include some of the most popular tourist spots, such as a large part of the Latin Quarter, the Montmartre hill and the Opera and Bastille districts.

Surveys and opinion polls show that French people have a split personality regarding cars. About two thirds prefer driving to work rather than using public transport, yet a similar proportion want cars permanently banned from the city centre.

Despite rising pollution from exhaust fumes, the French government has long shied away from confronting the motorist lobby.

Environment minister Dominique Voynet, the Greens leader, is campaigning for bolder action, and several cities last summer cut speed limits as heat waves pushedpollution to dangerous levels. They have yet to curb traffic levels.