Daimler was concealing the truth about the CO² emissions of its newest S-Class models, Germany's Deutsche Umwelthilfe e.V. (DUH) environment group said, as it filed the lawsuit with a Stuttgart court on Friday.

The environmental group claims that the energy efficiency of the high-powered gas-guzzling luxury models is lower than advertized in Daimler's promotion campaign for its latest car.

"The creativity of German carmakers in attempting to deceive customers about the efficiency and emissions levels of their cars apparently knows no boundaries anymore," said DUH executive Jürgen Resch.

German top-of-the-range automaker Daimler is currently running an advertising campaign with the slogan "Vision accomplished," portraying the newest S-Class models as friendlier to the environment than older its models.

However, Resch said DUH had found that the two with the most powerful engines exceeded the emissions levels advertized in the campaign by 11.3 percent and 11.1 percent, respectively.

Moreover, neither the S63 AMG 4Matic, nor the S63 AMG qualified for the energy efficiency classes given in the glossy ads.

Resch also said the group had decided to resort to legal steps after Daimler had rejected his request to immediately stop the ad campaign containing the false information.

The DUH noted that Germany's Volkswagen carmaker had immediately corrected false information when it had been caught cheating on emissions a few years ago.

uhe/kms (dpa, AFP, GLP)