Porsche is requesting a judicial review of London mayor Ken Livingstone's plan to charge high emissions cars £25 to enter the congestion charging zone.

It believes the £25 daily fee for owners of Band G cars which emit more than 225g/km CO2 is unfair. For residents in the congestion zone, who've previously paid 80p per day, it represents a 3025% increase.

Porsche GB managing director Andy Goss said: “A massive congestion charge increase is quite simply unjust. Thousands of car owners driving a huge range of cars will be hit by a disproportionate tax which is clear will have a very limited effect on CO2 emissions.”

Goss is writing to Livingstone this week. If there is no response, or the mayor refuses to reconsider his plans, Porsche intends to formally submit an application for a judicial review, which will challenge the decision.