ALL ministerial and Government cars are to be gradually replaced with vehicles which run on gas as well as petrol under an initiative aimed at encouraging use of greener fuels. The Government Car and Despatch Agency's fleet of 176 cars will be replaced with converted vehicles over the next six years at a rate of about 20 a year in line with usual three-year/ 60,0000-mile replacement cycles.

So far the only alternatively-fuelled vehicles run by the agency are a Ford Galaxy used by Prime Minister Tony Blair, which has been converted to run on liquid petroleum gas, and a Rover 800 also used by 10 Downing Street, which runs on compressed natural gas. The Agency runs Ford, Vauxhall, Rover, Jaguar and Land Rover models used by ministers, officials and VIPs. It also runs a fleet of vans, which does not feature in the conversion plans.

The cost of conversion varies between £750 and £3,000 depending on the model and whether LPG or CNG is used. Decisions on which fuel will be used in each case will take into account commercial considerations. However, the Agency says costs will be recouped through reduced vehicle management costs during the three-year fleet lifetime of each car - thanks to lower maintenance costs than for petrol vehicles.