While there may well be congestion arguments for restricting car use, the environmental emissions argument against cars as transport is, at best, questionable.

Zero emission cars are running on the roads now. Within a planning horizon of ten to 15 years, key industry figures reckon they will be the norm.

Planes, ferries and even trains and buses are, generally, greater polluters than cars.

A family of three or more are likely to be responsible for double the CO2 emissions emissions if they take the train rather than driving a typical medium-sized car.

On a ten-mile commute, four passengers in an average car are likely to produce half the CO2 emissions per head compared with taking a bus or coach instead. Drive a more efficient car, or have a less than full bus and presumably the environmental balance swings more favourably towards he car.

Studies in the UK and Germany have shown that travelling by public transport can be up to 60% less fuel efficient than travelling by car.

A Lancaster University study showed that, even when all seats were occupied, an express train from London to Edinburgh uses at least as much fuel per seat as a reasonably economical car! Again, use a more efficient car or have empty seats on the train and the balance will swing in favour of the car.

Motor manufacturers have hugely exceeded government targets for emissions reductions. CO2 emissions from new cars have been reduced by 10% over just seven years.

The average new car sold in 2003 emitted 9.3 per cent less CO2 than models registered in 1997. (Source: SMMT 2004)

Other emissions have been reduced even more radically. Emissions of nitrogen oxides, particulates and sulphur from cars in Britain has been cut by 97% in the last ten years. (Source NRDC)

CO2 emissions from road transport are already at around 15% of the 1983 figures and are continuing to fall.

According to the AA, one petrol lawnmower puts out more pollution than 100 modern cars.