The MEPs’ resolution also asked the Commission to set up a European certification authority that will oversee the work of the national type approval authorities to ensure independence from the car industry. Only cars randomly taken from the production line should be tested, MEPs concluded. Currently, national authorities only test ‘golden vehicles’ that are specially prepared for passing the tests, and no systematic checks take place afterwards.

Commenting on the decision Julia Poliscanova, clean vehicles officer at Transport & Environment, said: “If member states follow the advice of the European Parliament we will soon be breathing cleaner air in Europe. The proposals will stop the systematic cheating of tests by carmakers and the publishing of test results that are just hot air. The best way to solve the Dieselgate crisis is ambitious on-the-road tests to ensure cars comply with regulations in use, overseen by an independent EU-level body.”

The resolution follows the admission by Volkswagen that it skewed air pollution tests and the emerging evidence of ever-widening discrepancies between official test results and the real-world performance of cars on NOx as well as CO2.

Many member states are expected to reject the Commission's proposal to implement real-world testing at a meeting in Brussels. Particularly strong opposition is expected from Italy (home to Fiat), Spain (Seat) and Sweden (Volvo). Instead these member states want to set laxer limits despite experiencing illegal levels of nitrogen dioxide pollution.

Julia Poliscanova added: “It is time for member states to set regulations to clean up diesel exhausts instead of bending to the demands of carmakers. More than 600,000 people die prematurely every year as a result of breathing polluted air. The technology to clean up exhausts will cost just €100 for most cars. It is a small price to pay for clean air.”