Fleets keen to do their bit for the environment can order certain Viano and Vito models with the filters with immediate effect, although UK prices are yet to be announced.

The filters cut out many of the particulates from diesel engines that green campaigners claim are the cause of health problems such as pneumonia, emphysema and asthma. The filter can be ordered on Viano 2.0 CDI 109bhp and 2.2 CDI 150bhp models, as well as corresponding Vito 111 and 115 CDI versions with a Euro IV classification.

Deliveries will start in January 2005. In Europe, the filter will cost E695 plus VAT, so expect UK prices around the £500-£600 mark.