BERLIN, May 8 (Xinhua) -- German carmaker Audi is suspected by the Federal Motor Transport Agency (KBA) of having installed a previously-unknown emissions cheating technology in diesel versions of its A6 and A7 models, German magazine SPIEGEL reported on Tuesday.

"The KBA has commenced with an official hearing on suspicion of an illicit defeat-device installed in Audi V6TDI vehicles of the model series A6 and A7," a statement of German transport ministry cited by the magazine read.

The report put the number of affected diesel vehicles which had been sold by Audi at a minimum of 30,000 in Germany and another 30,000 in the rest of the world.

The Ingolstadt-based luxury carmaker responded to the allegations by announcing that it would release a detailed statement on the matter in the course of Tuesday.

"The diesel crisis is not over for Audi. New recalls should not be interpreted as the consequence of inactivity but to the contrary of serious attempts to resolve the issue at hand" an Audi spokesperson told SPIEGEL.

Nonetheless, the development is likely to deal an unwelcome blow to the reputation and finances of the Volkswagen subsidiary. SPIEGEL wrote that Audi had halted production of all A6 and A7 diesel motors as a result of the KBA investigation and faced the risk of having to recall large numbers of cars already in circulation.

Speaking to the magazine, the German ministry of transport described the likelihood of a government ordered product recall in Germany as "very high".

Because the European Union wide registration for the A6 series had been issued in Luxembourg, the KBA was already in contact with its counterparts in the neighboring state on the Western German border towards that end.

The Audi A6 series is one of the carmaker's best-selling vehicles and enjoys popularity among senior government employees and business executives as an official vehicle in particular.