Tony Blair and John Prescott have petrol-guzzling Jaguars. The rest of the cabinet have 2.7-litre Rover 800s while ministers of state and under- secretaries are driven in Mondeos and Cavaliers, all with a two-litre capacity.
The Government Car Service's fleet of some 130 vehicles is not much of an advertisement for an administration pledged to the greening of Whitehall.
Which is why three government ministers - David Clark, the Chancellor of the Duchy of Lancaster, Mr Prescott, the Deputy Prime Minister and Secretary of State for the Environment, and Peter Kilfoyle, the cabinet office minister - will gather at Horse Guards Parade next Monday to announce that the vehicles are to be switched to run on compressed natural gas (CNG) and liquefied petroleum gas (LPG).
Mr Clark said: "It is a clear message of the Government's commitment to the greening of Whitehall. It shows that we can make sure that our transport needs also reflect the need to protect the environment."
CNG, it is claimed leads to a 43 per cent reduction in emissions of the smog-creating nitrogen dioxide, as well as reduced emissions of carbon dioxide (24 per cent) and carbon monoxide (76 per cent).
But according to Tony Bosworth, transport campaigner for Friends of the Earth, the alternative fuel also leads to an increase in emissions of hydrocarbons of approximately 30 per cent.
"We are not actually recommending that people do buy CNG cars," he said. "People are best off getting the smallest most fuel-efficient petrol-powered car, fitted with a catalytic converter."
Similarly with LPG, he said: "The emissions picture is mixed. you have reduced carbon dioxide and hydrocarbons but in this case higher emissions of nitrogen dioxide. When you compare it with a petrol-powered car the emissions benefits are not great enough to warrant people converting."
He pointed out that there were only nine roadside fuelling stations in Britain capable of supplying natural gas.
The Government Car Service, however, would supply its fleet from gas supplies at its own depot at Vauxhall, south London. Ministerial cars, which rarely leave the capital, would still be capable of using petrol in emergencies.
Labour will look to take credit for the alternative fuel initiative, although it was actually John Major, the former prime minister, who took charge of the first CNG-powered government car a year ago.
Many Labour ministers have already displayed their green credentials by eschewing their government cars in favour of public transport.
Mr Clark caused commotion among civil servants earlier this year when he was stuck on the District Line during a bomb scare on the London Underground. Clare Short, the Secretary of State for International Development, swears by the 77A which takes her up to Westminster from her home in Clapham, while Frank Dobson, the Secretary of State for Health, even took the 24 bus to Downing Street when the Prime Minister offered him the job.Reuse content