(Bloomberg) -- Germany presented its first diesel bus with a technology designed to slash air pollution as it steps up efforts to avoid a ban on older public transport on city roads.

The bus, which operates in Dusseldorf and is owned by the Rheinbahn AG, is equipped with a so-called Selective Catalytic Reduction device, the Transport and Digital Infrastructure Ministry said in Berlin on Friday. The device can convert as much as 90 percent of the vehicle’s armful nitrogen oxide emissions into innocuous oxides.

The ministry is hoping for a quicker uptake of its offer to help finance the catalyser upgrade after a regional court in February allowed municipal governments to ban on older diesel vehicles within city limits. Hamburg in June was the first region to follow up the ruling, banning vehicles on a busy road with certification lower than the Euro VI standard for emissions.

“Our aim is clear -- we want to avoid a general ban in German cities,” Transport Minister Andreas Scheuer said in the ministry statement.

The government and cities need to speed up fitting diesel upgrades, said the Environmental Action Group DUH, a group pushing to ban older diesels from the roads. As many as two-thirds of Germany’s 35,000 municipal buses are diesels.

Just 1,000 applications for catalytic upgrades for buses have been made to date, costing 8.5 million euros ($10 million), according to Scheuer’s ministry.

To contact the reporter on this story: Brian Parkin in Berlin at bparkin@bloomberg.net

To contact the editors responsible for this story: Reed Landberg at landberg@bloomberg.net, Andrew Reierson

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