The cost of owning a 4x4 is turning buyers away, say the Green Party

There were 3,172 sold between January and May, down from 3,402 in the same period last year, said the Society of Motor Manufacturers and Traders (SMMT).

This amounts to a 7% fall in sales of 4x4s in London, compared with 5% drop nationally, their report said.

The Green Party said the steeper fall in London reflects motorists' expectation of higher charges for 4x4s.

Environmental impact

London Mayor Ken Livingstone wants to raise the congestion charge for the most polluting vehicles, which include some 4x4s, to �25.

Several local authorities have introduced or are considering higher parking fees for so-called gas-guzzlers.

And last year, the government raised vehicle excise duty for the most polluting petrol-fuelled cars to �210.

Darren Johnson, of the London Assembly Green Party, said such measures were forcing people to think carefully about the cars they buy.

He said: "Londoners are obviously thinking twice before buying gas-guzzlers because they understand that less polluting cars are good for the climate and good for their wallet"

Sheila Ranger, of the RAC Foundation, said motorists were now taking environmental factors into consideration.

"For some motorists, 4x4s are essential, such as people in rural areas or workers who need extra space," she said.

"But those for whom it's a lifestyle choice, we are noticing more and more are now more conscious of the environmental impact."