If live are in London and your vehicle belongs to the band G, i.e. emit more than 225 grams of CO2 per kilometer then you will have to pay £25($50) every day to enter the congestion zone. This will obviously affect those who own heavy 4×4 vehicles. Most other vehicles will continue to pay the daily charge of £8 ($16). As it is London charges a tax, known as a congestion charge, on almost all vehicles that enter central and parts of west London, however hybrids or eco-friendly fuel cars are exempt. London Mayor Ken Livingstone made this announcement in his mayoral re-election campaign.

This directive has irked the Automobile Association. They dispute that the charge will come down like a ton of bricks on small business owners who use vans to conduct business in the city, as well as large families who must use bigger vehicles to travel.

Source