A court in Leipzig will rule on whether cars will be banned from German city centres.

A court in Leipzig has delayed a ruling which could see major German cities banning the use of diesel cars in central urban areas.

German state governments have started appeals after local courts in Stuttgart and Düsseldorf imposed bans because of poor air quality. The ruling, which could affect the resale value of as many as 15 million cars in what is Europe's biggest car market, is now set for 27 February.

When asked about the delay, judge Andreas Korbmacher said: 'We still see a considerable need for guidance,' indicating that he would be speaking to colleagues at the European Court of Justice on the matter.

The court decision is a hot political issue in Germany at the moment – diesel sales have slumped to a third of new car sales in the country and many see a city centre ban on the engines as the final nail in the coffin for the fuel. Angela Merkel's government has already proposed new initiatives around the country where free public transport will be provided for citizens as a conciliatory measure.

While the ECJ has yet to speak out on the issue, European Commission spokesman Margaritis Schinas said on Thursday that the European Union didn't necessarily see the issue as within its jurisdiction: 'We don’t view this as a case when we have community competence or we have something meaningful to offer.'

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The move to outlaw diesels in major cities comes in the wake of the Dieselgate controversy, and follows indications from a number of major European cities that they planned to outlaw traditional petrol and diesel cars from central areas. Paris, Madrid, Mexico City and Athens are planning to ban diesel vehicles by 2025, while Copenhagen's mayor wants to outlaw new diesel cars from entering the Danish capital as early as next year.

Environmental group DUH is behind the push to ban diesels in German cities, and is trying to get more cities to sign up. The Leipzig court's ruling will determine whether local councils are effectively allowed to make those decisions. 'Everything is still open, but we are much more optimistic,' DUH chief Jürger Resch said. 'We are convinced that the court will make its own decision. And we also want a national decision.'

A possible ban would prove to be an embarrassment for the German government which is committed to the country's automotive industry, and has often promoted the use of diesel cars in a bid to reduce carbon dioxide emissions. The government has been against city centre bans on diesels, fearing a backlash from drivers and a strain on public transport networks.