Traders lose £1m a month

The congestion charge has damaged trade in central London, Ken Livingstone's own research admits.

But the Mayor's economists put the cost to business at "only" £50,000 a day, or £ 1million a month, and say it is insignificant compared with the 11-week closure of the Central line and the post-Iraq war downturn in tourism.

However, the figures, compiled by the GLA's economics unit, will be seized on by opponents of the £5-a-day charge as evidence of its damaging effect on London's economy.

According to the analysis, the charge deters up to 30,000 shoppers a month from entering the West End. Overall, 60,000 fewer cars than before are entering the zone each day.

The GLA unit says the figure of £1 million a month for the loss to businesses compares with the £125 million a month caused by the drop in tourism and £7 million caused by the breakdown in service on the Central line earlier this year.

But a spokesman for the London Chamber of Commerce said: "The group that's been hardest hit is smaller retailers. A relatively insignificant drop in takings can have a devastating effect on them."

Mr Livingstone has always insisted that any downturn in business needs to be compared to the damage formerly caused by congestion.