The borough's politicians are concerned that Barnet will turn into 'a giant car park' once congestion charging comes into force on February 17 next year.

Ken Livingstone formally approved the scheme on Tuesday, which means anyone driving into central London between 7am and 6.30pm on weekdays will have to pay £5.

Conservative Councillor Brian Coleman, Barnet's GLA member who actively opposed the scheme in the London Assembly, believes commuters will park in Barnet and travel into the charging zone on public transport. "It will turn Barnet into a giant car park," he said. "Motorists pay through the nose already."

Labour's Barnet Council leader, Alan Williams, said: "I remain supportive in principle. But introducing congestion charging without first resolving the situation for areas outside the central zones will simply lead to chaos across boroughs such as Barnet."

He added that taxpayers should not have to fund controlled parking zones around train stations, which he says are needed to reduce the impact of the scheme.

The Mayor is due to raise at least £130million a year from the scheme money which, by law, will improve public transport in the capital.

A spokesman for Transport 2000, the national environmental transport campaign, said: "Congestion charging is essential to pay for improved public transport. We can expect traffic to drop by 10-15 per cent, which will free up the roads for a much better bus service."

The Government could still order a public inquiry into the scheme.

Key facts:

- The congestion charging zone will run from Euston Road down to Elephant & Castle and from Hyde Park to the Tower of London

- The charge will be paid in advance by internet, phone or in shops, and logged on a central database

- 700 CCTV cameras will scan every vehicle crossing the zone boundary and check the number against the database. Those who have not paid will be fined £80, reduced to £40 for a swift payment. The penalty will rise to £120 for late payment

- More cameras inside the zone will catch vehicles that have stayed inside the boundary