A quarter of businesses are considering leaving central London

According to Westminster Council, more than 50% of the 400 businesses located within the charge zone who responded to the survey, say ending it at lunchtime would reduce its effect.

Around 70% said they had suffered a loss of income.

Councillor Colin Barrow, of Westminster City Council, said he had written to London Mayor Ken Livingstone about changing the charge.

He told BBC London: "Ken Livingstone and Transport for London are charging admission to central London, we are the only major city in Europe to do that."

But Mr Livingstone says the real reason for profit losses is a general economic slowdown.

He challenged the council's survey claiming it contradicted previous research.

But the survey added that a quarter of the companies included were considering moving away from central London.

The charge was introduced in February and motorists are charged �5 to drive in the zone between 7am and 7pm.

Businesses want the charge to finish at 1pm.