German NGO Environmental Action Germany (DUH) says a court ruling in Stuttgart on banning certain diesel models from entering the inner city showed the bans were “justified” and “unavoidable”.

The group that originally filed the lawsuit said the ruling has to become effective by the beginning of 2018 at the latest, writes cleanenergywire.org.

The court said that voluntary software updates for vehicles with manipulated emissions were inappropriate for protecting public health, warranting “immediate” action to reduce NOx levels in the city, the DUH said in a press release.

DUH head Jürgen Resch called on Winfried Kretschmann, Green state premier of Baden-Wuerttemberg, to accept the ruling “for the sake of Stuttgart’s people”.

Kretschmann told journalists on Monday his government would wait for the court’s statement before deciding whether to file an appeal.