The issue of filters has been brought to the fore in the UK by the Inland Revenue, which says diesels will be subject to a 3% penalty under the new benefit-in-kind tax laws in order to take account of the harm diesels are said to cause in towns and cities through particulate emissions .
Peugeot and Citroen have said that their commitment to filters will make such a policy redundant. However, Yves Dubreil, Renault's car programme manager, said: 'Such technology would add 10% to the price of a car. This is too much.' He said greater efforts should instead be placed on preventing pollution by older cars.