The European Automobile Manufacturers’ Association (ACEA) has said new real-world emissions tests will mean a “substantial number” of diesel models will have to be phased out earlier than planned.

The European Union has voted to adopt tougher emissions tests for new models of cars to better reflect real-world driving conditions from September 2017.

New car models sold after September 2017 will not be allowed to exceed nitrogen oxide emission levels by more than twice the technical limit.

Car makers will have until 2019 to limit the emissions on all new vehicles to that level.

By 2020, the emissions from all new models must not be greater than 1.5 times the technical limit. The same rule will apply to all new vehicle from 2021.

The ACEA said that while its members understand the need for real driving emissions (RDE) testing, it said the the deadline would be “extremely difficult for automobile manufacturers to reach in a short space of time”.

The ACEA said: “As a direct consequence, a substantial number of diesel models will have to be phased out earlier than planned.

“As well as having serious economic implications, this will make it more challenging for manufacturers to meet the 2021 targets for CO2 emission reductions, since diesel engines emit 15-20% less CO2 than comparable petrol engines.”

The purpose of the new RDE test procedure is to bridge the gap between the current regulated testing of emissions using a laboratory test and conditions experienced on the road.

Erik Jonnaert, ACEA secretary general, said: “RDE testing of cars on real roads under realistic driving conditions will be a new addition to the existing test requirements, making Europe the only region in the world to implement such real world testing for cars.

“Over the past years, policy initiated by the EU institutions has focused on reducing greenhouse gas emissions, resulting in the most stringent targets for CO2 emissions from passenger cars in the world.

“The automobile industry is ready to engage with Europe’s policy makers to examine how to reconcile higher air quality standards with ambitious climate change policies.”