The SMMT hopes the European Commission can quickly resolve an internal clash that threatens the implementation of a regulation to cut CO2 emissions.

A decision to force carmakers to conform to an across-the-range average of 130g/km by 2012 – or face hefty fines – has been ruled illegal by the EC’s legal affairs committee.

At issue is which section of EU law making is decisive. It was drafted under Article 95, which is intended to prevent market distortions.

But the legal committee reckons it should come under Article 175 because this deals with the environment. 

An SMMT spokesman said: “The European Commission and member states have specifically developed the new car CO2 regulation under Article 95 to guarantee its uniform application across the EU. This decision was recently endorsed by the EU’s industry committee.

“The legal committee’s opinion will doubtless help to test the robustness of the regulation. 

“Article 95 is the only realistic basis that can deliver a sustainable outcome for this important regulation.”

Sources in Brussels say the proposed 130g/km law has created heated disagreements.

Left-leaning MEPs pressing for tough rules to cut CO2 emissions have been infuriated by members of the industry committee tabling amendments to tone down pollution limits, allow manufacturers more time and reduce fines for offenders.

MEPs from EU countries with substantial investment from carmakers have been pressing the point that manufacturers are investing heavily and working hard to make cars cleaner.

The environment committee will consider the views of the legal committee but the matter should be resolved on October 20 when the European Parliament is scheduled to make a final decision.

An executive of a carmaker with above-average CO2 credentials said: “The industry has developed its own momentum to deal with CO2 emission issues, and whatever the EC does is unlikely to make much difference.”