The announcement by the European Commission’s Environment Committee also saw the call from MEPs for indicative targets for post-2020 CO2 emissions, with a range of 68-78g/km from 2025.

These emission limits are the average maximum allowed for car makers registered in the EU. Makers producing fewer than 1,000 cars a year should be exempt from the legislation, say MEPs. Carmakers would therefore have to produce, in addition to older, heavier or polluting models, enough cleaner ones to achieve a balance of 95g by 2020, on pain of penalties.

The changes would also see clean car innovation encouraged by giving "super-credit" weightings to each carmaker's cleaner cars that emit less than 50g of CO2. Within each manufacturer's "balance", each of these extra clean cars would count as 3.5 cars in 2013, falling to 1.5 from 2016 and 1 from 2024.

Any increase in the emissions target for each manufacturer deriving from the “super-credits” calculation would be capped at 2.5g. MEPs also say it should not be possible to transfer any unused super-credits from one year to another.

The committee also covered the subject of more reliable testing procedures, noting that recent studies show that manufacturers have exploited weaknesses in today's procedure for testing cars' environmental performance, with the result that official consumption and emission figures are far from those achieved in everyday driving conditions.

As a result, MEPs said that the new UN-defined World Light Duty Test Procedure (WLTP) should replace today's procedure in EU law "as a matter of urgency", and if possible by 2017, on the grounds that the WLTP better reflects the real conditions in which cars are used.

In response, European carmakers association, the ACEA said that policy makers should not lose sight of the fact that Europe and its automobile industry play a leading role in the global challenge to reduce CO2 emissions.

It added that the existing European CO2 emissions targets for 2015 and those proposed for 2020 are the most stringent worldwide, far more challenging than those in the US, China or Japan.

The ACEA also says that sales and jobs in the sector have been declining for over six years.

‘This year has also got off to a worrying start, as our most recent new car registration figures show that the first quarter of 2013 is the worst first quarter on record,’ said ACEA secretary general Ivan Hodac.

‘In this difficult economic context – and given the fact that the regulatory pressure in Europe is already far higher than in our major competitor regions – the outcome of the ENVI Committee vote sends a worrying signal for the future of the industry in Europe. The risk is of increased manufacturing costs in Europe, creating a competitive disadvantage for the region. In effect, the ENVI proposals would jeopardise the industry’s ability to retain its technological and environmental lead.’

The ACEA also said that the setting of long-term targets is a particular concern.

‘By setting unrealistic and politically motivated long-term targets without a scientific basis, MEPs have taken a dangerous short-cut,’ Mr Hodac concluded. ‘They are also disregarding commitments made to the industry in the Commission’s CARS 2020 Action plan regarding “smarter regulation” based on sound impact assessments.’

ACEA also calls for more effective “super-credits”, which it says are being used far more strongly in other world regions, such as USA, China and Japan.

‘Again, why should Europe operate in a vacuum?’ questioned Mr Hodac.