9.9mph London's record low traffic speed

Traffic in central London now crawls along at 9.9mph - the lowest speed recorded since the horse-and-cart era.

Official figures today show that commuters spend more than half of their time in the capital's centre at a standstill.

Ken Livingstone seized upon the figures as evidence that London desperately needs congestion charging, due to start in a year's time.

Motoring groups, however, claimed the figures showed the adverse impact of traffic-calming schemes, additional bus lanes, 20mph zones, speed cameras and cancelled buses.

According to the Mayor's Transport for London (TfL) office, which compiled the figures, at least two per cent more drivers - around 2,000 - now force their way into central London each working day compared to 1999. A further additional two per cent are coming in by motorcycle, bus, Tube and DLR.

Derek Turner, managing director of TfL street management, said: "London simply cannot afford to let traffic speeds continue to drop."

However, Paul Watters, the AA's head of policy, said: "The rise in car journeys is far lower than the figures suggest. Speeds are down because of a number of factors including better speed enforcement. "