The current charge is �5

Mr Livingstone has asked Transport for London (TfL) to begin consulting on a �3 increase for a private car to enter the central zone.

He added the earliest the proposed change could be introduced would be July next year.

But he said he wanted the charge for "commercial fleet vehicles" to rise to just �7.

Mr Livingstone said: "The congestion charge has been an unprecedented success in dramatically reducing congestion, pollution and accidents.

MAYOR'S PROPOSALS A rise in the charge from �5 to �8 A 15% reduction for those paying monthly or annually by giving annual payers 40 free days and monthly payers three days free Amending the current fleet scheme by reducing the number of vehicles needed to participate from 25 to 10 and allowing cars to be counted as well as vans and lorries A freeze in the late payment fee levied between 10pm and midnight at �10 Reducing the charge for registering a change of car Increasing the number of petrol stations where the charge can be paid

"We need to maintain and build upon this.

"I am proposing one large increase in this mayoral term to maintain the effectiveness of the charge and raise additional revenues to further reduce congestion as part of TfL's �10bn, five-year investment programme."

Mr Livingstone said the proposed increase would be accompanied by a raft of measures aimed at reducing the "hassle" of paying the charge.

The congestion charge, which was introduced in February 2003, has been credited with reducing congestion in central London by 30% with 70,000 fewer vehicles entering the zone.

It raised �79.8m in its first year and was projected to raise about �100m in subsequent years.

According to the mayor's office, the proposed rise in the charge would bring in an extra �50m to �60m per year and see traffic numbers cut by a further 5%.

But Angie Bray, from the London Assembly Conservatives, said: "This rise will be bad for business, bad for key workers such as teachers who have to enter the zone, and bad for all hardworking Londoners who already pay too much tax."

And the Liberal Democrats' Lynne Featherstone, chair of the London Assembly Transport Committee, said: "This price hike has nothing to do with reducing congestion but everything to do with raising a bob-or-two."