From Bernard Brewer

SIR. The London Assembly Lib Dems want drivers of 68 "models" of 4x4 vehicles to pay double the congestion charge because they emit more carbon dioxide than cars (Surrey Comet, June 15). It appears that this number relates to all 36 models that have carbon dioxide emissions of more than 200 grams per kilometre.

There are more than 100 models of cars and MPV's with more than 300 versions that also have emissions exceeding this figure. To state that 4x4s emit more CO than cars is being economical with the truth. There is no reason why such vehicles should incur a higher charge.

BERNARD BREWER Kingston Vale