The decision will strip about 36 members of Transport for London, the new transport authority for the capital, of their company cars. A total of 49 staff are entitled to a new car, but several have opted for a cash for car scheme already offered. Incentives are also paid for choosing smaller, more fuel-efficient vehicles, which are all supplied on a three- to four-year lease.
Transport for London does not yet control London Underground, which has about 200 staff provided with company cars, but they will be affected when control passes to TfL next year.
Dave Wetzel, vice-chairman of Transport for London, said: 'London's new mayor is very keen that senior managers we employ to provide better transport should get out of their company cars and on to the public transport system. In this way, they can share the frustration and delays that our passengers face on a daily basis and use this experience to improve services and help make travel better for all of us.
'We also want other employers to reconsider their provision of company cars so that we can all breathe less polluted air, suffer fewer road accidents and reduce congestion in our lovely city.'
However, in London, company cars are not primarily responsible for causing the pollution. Senior environmental chiefs have already blamed pollution on the buses and taxis. Oxford Street - designated a car-free zone - is one of the most polluted streets in the country, according to both Friends of the Earth and Westminster City Council.
However, a spokeswoman for Westminster City Council said: 'Research carried out four to five years ago shows that the road was one of the most polluted in London because of all the buses and taxis, which are high emission vehicles.'