CHANCELLOR of the Exchequer Gordon Brown is under pressure both to consider an environmentally-based car purchase tax, and to introduce a graduated vehicle excise duty in his Budget on Tuesday. The House of Commons Environmental Audit Committee made the introduction of a graduated reduced VED one of the key recommendations of its fourth report.

'We believe the types of tax incentives being considered and introduced by the Government give useful incentives towards the purchase of cleaner vehicles or their conversion to take cleaner fuels, if they are set at an appropriate rate,' it said. 'However, we have been disappointed at the low rates proposed for the incentives and that the Government does not appear to have given any consideration to the role of a car purchase tax in providing appropriate incentives.'

The EAC was following up on the Chancellor's announcement in his last Budget that the Government would cut the £150 VED by £50 for 'smaller and cleaner' cars. This opened a fierce debate about what constituted a 'green' car, particularly in the light of the Kyoto conference's focus on cutting emissions of the greenhouse gas carbon dioxide.

By this measure, Department of the Environment, Transport and the Regions' own figures show that diesel powered cars are the cleanest on UK roads - and that the Volkswagen Passat TDi was 'greener' than a Citroen Saxo 1.0 - despite concerns expressed by the Review of the National Air Quality Strategy about the role played by diesel particulate emissions in urban pollution.