The Mayor of London is planning to triple the capital’s congestion charge for 4x4s and cars with high carbon dioxide levels.

Greener cars (emitting 120 g/km or less) could be considered for a discount on the normal £8, where as ‘environmentally damaging’ vehicles (any cars emitting more than 225 g/km) will have to fork out £25.

The discounts will introduce in 2008 and the higher rates will come into force by 2010.