BERLIN, April 3 (Xinhua) -- The newly-installed German minister for environment Svenja Schulze (SPD) has urged carmakers to commit to costly technical upgrades for vehicles affected by the "dieselgate" scandal, the newspaper BILD reported on Tuesday.

Schulze told BILD that the automotive industry had a responsibility to help lower nitrogen oxide emissions levels in German cities. She complained that carmakers had "massively cheated" customers by selling cars with "extremely high emissions levels."

The SPD-politician argued that technical upgrades of diesel motors offered a promising means of lowering excessively high nitrogen oxide pollution levels in densely-populated areas. However, carmakers would have to carry out such changes "at their own cost."

In spite of a leaked Volkswagen report which described technical upgrades as "feasible" for 70 percent of diesel vehicles sold by the company prior to 2016 and a more recent government analysis which reached a similar conclusion, German carmakers have repeatedly insisted that such measures would be too costly to merit serious consideration. Industry representatives have instead committed to cheaper and less effective software upgrades for customers.

However, a landmark ruling by the Federal Administrative Court has empowered municipal governments to resort to an even more radical course of action by imposing driving bans on heavily-polluting diesel vehicles unilaterally. Amongst others, the verdict was influenced by a belief amongst judges that agreed software upgrades would not be sufficient to guarantee citizens' right to clean air.

According to the Federal Environmental Agency (UBA), diesel cars are responsible for more than 50 percent of harmful nitrogen oxide emissions. The EU has threatened to sue Germany before the European Court of Justice unless the situation is addressed swiftly.

Nevertheless, the new transport minister Andreas Scheuer (CSU) has since repeatedly sought to dispel growing fears among diesel owners and carmakers of looming driving bans. Speaking to the "Funke" media group on Tuesday, Scheuer expressed optimism that driving bans could still be prevented.

Scheuer admitted that software updates would not be enough to lower nitrogen oxide pollution in German cities beyond EU regulatory limits but argued that they could still make an important contribution to improving the situation in the short-run. Around 5.3 million cars would receive such updates by the end of the 2018, including ambulances, busses and garbage trucks.