The hometown of Mercedes-Benz and Porsche is bracing for a ban on diesel cars starting as soon as January 1.
A judge in Stuttgart, Germany, ruled on Friday that the city may have to ban or severely limit diesel cars to bring down pollution and meet air quality standards.
The ruling was triggered by a lawsuit filed by Environmental Action Germany and ClientEarth. They have filed similar suits in cities across Germany, calling for diesel car bans.
Judge Wolfgang Kern found that Stuttgart's current clean air plan was insufficient. He said in court that "the protection of health has to be regarded as more important than the right to property and the general freedom of action of the vehicle owners concerned."
The German state of Baden-Württemberg is expected to appeal the ruling to the country's highest court.
"The judge has clarified that a diesel ban is unavoidable. Stuttgart's authorities must now find rapid and effective ways to solve the region's air quality issues," said Ugo Taddei, a lawyer at ClientEarth.
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Authorities around the world have been trying to clamp down on pollution from gas and diesel cars for years. They've introduced tougher standards to cut emissions and slow global warming.
Pressure for change increased after Volkswagen (VLKAY) admitted in 2015 that it had been cheating on diesel emissions tests. Vehicles were emitting up to 40 times the legal limit on nitrogen oxide.
The Paris climate change agreement has also spurred governments into action. The U.K., France and Norway recently announced plans to cut back on gas-guzzlers to promote electric and hybrid cars.
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The fallout from Volkswagen's "dieselgate" scandal continues. Porsche, part of the Volkswagen (VLKAY) group, has just been ordered to recall tens of thousands of diesel SUVs after German officials said they were equipped with an "unauthorized defeat device" allegedly used to cheat emissions testing.
Daimler (DMLRY), the firm that makes Mercedes-Benz cars, announced a voluntary recall earlier this month of more than 3 million diesel vehicles in Europe.
The automaker is offering European owners a free service upgrade that would improve emissions. It is also introducing a new diesel engine across its model range.
"The public debate about diesel engines is creating uncertainty," CEO Dieter Zetsche said last week. "We have therefore decided on additional measures to reassure drivers of diesel cars and to strengthen confidence in diesel technology."
Daimler told CNNMoney on Friday it believes a ban on diesel cars is a bad idea because it would hurt the economy, trade and commuters.
"In our view there are other measures that could contribute more easily, effectively and faster to the reduction of particulate matter and nitrogen oxides," the company said in a statement.
Related: 'Made in Germany' put to the test
Next week, the heads of Volkswagen, BMW (BMWYY), and Daimler will meet government ministers and labor unions in Berlin for a summit to discuss reducing diesel pollution.
It's an attempt to head off bans of the kind that now looms in Stuttgart.
The city in southwest Germany is home to the headquarters of Daimler, Porsche and automotive parts group Bosch.
-- Sally Manuela Eshun contributed to this report.
