Germany's KBA vehicle authority is probing concrete suspicions that the affected cars were fitted with illicit defeat devices designed to manipulate emissions levels, the magazine said, without citing sources.

Daimler said on Friday it had not received a formal summons from KBA regarding its C-Class and G-Class models, a precursor to a recall, but declined to comment in detail on the Spiegel report.

The report comes a day after the KBA ordered Daimler to recall the Mercedes Vito van model fitted with 1.6 litre diesel Euro-6 engines because of engine control features to reduce exhaust emissions which KBA said breached regulations.

Daimler has said it is appealing the KBA findings on the Vito and will go to court if necessary.

Since rival Volkswagen admitted in 2015 to cheating U.S. emissions tests, German carmakers including VW, Daimler and BMW have faced a backlash against diesel technology in which they have invested billions of euros.

After news of the Vito recall emerged, German Transport Minister Andreas Scheuer summoned Daimler Chief Executive Dieter Zetsche to a meeting on Monday, a spokeswoman for the ministry said.

He also asked the KBA to pursue any further leads related to emissions at Daimler's Mercedes-Benz premium brand.

The KBA declined comment.

(Reporting by Andreas Cremer and Markus Wacket in Berlin and Ilona Wissenbach in Frankfurt; Editing by Edward Taylor and Adrian Croft)