Hundreds of thousands of motorists across the West Midlands face being stung by the Government’s controversial “retrospective” car tax hike on the most polluting cars, new figures reveal today.

In the West Midlands Metropolitan area alone – the Black Country, Birmingham and Coventry – 154,355 motorists could be hit with the tax hike, with a further 63,275 in Staffordshire and 30,704 in Shropshire. The changes, due to come into effect next year, will mean cars will be put in one of 13 bands based on emissions.

The new rates will affect vehicles purchased from 2001 – therefore penalising people who bought their cars without any idea they would one day face a big rise in duty.

Today, a car that produces between 186 and 225g/km of CO2, such as a Land Rover Freelander diesel 2.2 TD4 GS – one of Britain’s five most popular cars – or a Peugeot 407 Saloon 2.0 Auto, would incur an annual tax of £210 – a rise of £60.

The owner of a car such as a Land Rover Sport Auto 3.6, which emits more than 225g/km of CO2 is taxed at £400.

Under the proposals, drivers of such cars registered after March 2001 – of which there are 363,975 in the West Midlands – would see their tax rise by between £15 and £90 in 2009.

And the net is much wider, for these latest figures from the Department for Transport only detail the number of licensed cars by carbon emissions in the current top two tax bands.

Cars that emit 161g/km or more will be subject to an increased levy under the new structure.

A Treasury spokesman said the move would encourage more people to use more environmentally-friendly cars as well as save 1.3 million tonnes of CO2 by 2020.

But the Tories have branded it a tax grab, rather than an attempt to make people buy greener cars.

AA president, Edmund King, said: “This is not sending out a green signal but a mean signal and is penalising many families who cannot afford to change their car.”