In a New Year message to employers, he said: 'LPG is an option which has already removed thousands of motorists from uncertainty about pump prices. The Government has backed the LPG alternative and I hope that many more motorists will consider it.
'LPG is half the price of petrol. It emits fewer greenhouse gases and is therefore one of the most environmentally- friendly options currently available.
'It is a 'win-win' fuel. While helping the environment, motorists will also be saving considerable amounts of money, especially if they travel long distances. That is why I want fleet managers, car hire firms, taxi companies and individual motorists to explore the LPG option.'
In a second wave of encouragement to switch to the fuel, Calor Gas has written to 5,000 fleet decision-makers calling on them to consider converting their vehicles to run on LPG.
A spokesman said: 'There are substantial grants available for conversion of existing vehicles as well as an impressive list of manufacturers which offer LPG models. Also, there are now more than 1,300 retail outlets for LPG.'
There are also just weeks to go before the launch of congestion charging in London on February 17, which some in the motor industry believe could spark a dramatic rise in the popularity of LPG.
A fleet of just 20 vehicles that switches to LPG, which receives a 100% discount on the £5 a day charge, could save £30,000 a year on tolls, Calor claims. That would be in addition to savings on fuel, with one 270-vehicle fleet reporting a £200,000 a year saving on fuel costs by converting to LPG.