The congestion charge has done little to affect jams in London over the five years it has been in place, official figures have shown.
Transport for London (TfL) statistics reveal the number of cars coming daily into the original charging zone and into the western extension has fallen, but widespread streetworks and traffic management schemes have greatly reduced the road capacity in both zones.
This has resulted in congestion returning to levels experienced before the charge was brought in.
London Mayor Boris Johnson said that he had asked TfL to accelerate the delivery of his plans to improve traffic flow.
These include allowing motorbikes to ride in bus lanes, rephasing traffic signals and cracking down on delay-causing streetworks by utilities.
The TfL report said that traffic in central London was 21% lower than pre-charge levels and traffic entering the western extension (introduced a year ago) was 14% down.
Mr Johnson said: "I have always thought that the congestion charge is a blunt instrument. It has proved successful in cutting traffic coming into London but on its own has not resolved the problem of congestion. Various works and schemes going on in the capital have also eroded its impact."
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