New diesel cars could rise in price by up to £600 due to air quality limits in forthcoming Euro V and VI emission standards, supported by a vote in the European Parliament this week.

To meet Euro V particulate limits, even the smallest car would require the addition of a particulate trap to the exhaust system.

The Society of Motor Manufacturer’s and Traders believes that the possible price rise will make diesels less attractive to buyers. This will make more customers turn to petrol variants which can be up to 30% worse for fuel consumption and carbon dioxide emissions. The SMMT said the price hike could threaten to halt what the European Commission recently described as the 'significant progress' made by car makers in cutting CO2 output since 1998. Estimates suggest the resultant CO2 penalty could be as high as 6%.

"Urban air quality problems are not caused by new cars”, said SMMT chief executive Christopher Macgowan.

“Today's models are around 95% cleaner on things like diesel particulates than models sold 15 years ago. The truth is that air quality problems come from older and poorly maintained vehicles and by poor traffic management.

“The dark side of Euro V and VI limits is the impact on CO2 reduction targets. We should therefore re-affirm the importance of proper impact assessments on all new legislation, one of the key recommendations made by the high-level CARS21 group in its report last year. We must also make it clear that factors outside the motor industry's control may continue to skew the progress we have made on bringing cleaner models and new technologies to market.”