German car industry can't be trusted, says EU commissioner

"One has to question the ethical behaviour of the German car industry," Bienkowska added.

Last month, it was revealed in a new documentary series, Dirty Money, that Volkswagen, BMW, and Daimler had financed a research institute which forcibly tested the health effects of diesel emissions on monkeys in the United States.

Days later, German newspaper Sueddeutsche Zeitung reported that experiments were done on volunteer human test subjects in Germany.

The tests were done with the aim of proving that the diesel fumes were not toxic.

The revelations came two-and-a-half years after it was revealed that the German Volkswagen Group (VW) had equipped millions of diesel cars with cheating software.

In her speech, Bienkowska called the scientific tests "a new and a much sadder dimension" of the German car industry's behaviour.

"This is the second time that the car sector showed that it is completely untrustworthy," said Bienkowska.

"When I first heard it, I frankly couldn't believe it," she said.

The Polish commissioner said she doubted that only a handful of employees in the German car companies knew about the tests.

According to Bienkowska, Germany's car industry has "systemic problems".

She noted that German authorities were investigating the human tests, which happened in the German city of Aachen.

MEPs from all sides of the political spectrum on Monday evening reacted to the scandal and noted the car companies involved lacked a moral compass.

Centre-right German MEP Peter Liese said the experiments on animals were "completely unacceptable".

Belgian centre-left MEP Kathleen Van Brempt, who was the chairwoman of the parliamentary inquiry into the Dieselgate emissions scandal, criticised the reported attempt to influence scientific research.

"That reminds us of the tobacco industry. Remember when they paid for so-called independent research, to say there are no hazardous substances in cigarettes," she said.

However, MEPs also asked the commissioner to do more than condemn the car industry.

"We need action," said Van Brempt.

She referred to the millions of diesel cars, designed to only be fully clean during official tests, still driving on European roads.

Luxembourgish Green MEP Claude Turmes added that the real scandal was that these cars were still allowed to be on the road.

Their Dutch Liberal colleague, MEP Gerben-Jan Gerbrandy, also noted that the biggest scandal was that EU member states are allowing the car industry to cheat.

"Where are the German fines for Volkswagen? Where are the British fines for Skoda? Where are the Italian fines for Fiat?" said Gerbrandy, referring to the respective national authorities responsible.

Last year, the commission triggered its enforcement tool known as the infringement procedure, telling the responsible EU member states to slap fines on cheating carmakers.

Bienkowska said on Monday that the commission was still analysing responses by member states, which included Germany and the UK, but that she was prepared to take the next step in the procedure, which could end up in the Court of Justice of the EU.

"We are not ready for this yet," she noted.