THE western extension of London's congestion charge came into force at 7am this morning - to the dismay of local residents and businesses.

The zone has roughly doubled in size and the £8-a-day toll will now include areas such as Kensington, Chelsea, Notting Hill, Bayswater, Brompton, Belgravia and Pimlico.

The hours for the congestion charging scheme have also changed and will finish half an hour earlier at 6.30pm.

Transport for London said that all the monitoring systems were operating correctly and all the payment channels were up and running.

Bus services in west London have been increased from today and TfL said it was currently running a good service on all Tube lines, except the District and Circle lines.

London mayor Ken Livingstone claims it will cut traffic levels in west London by 10 to 15% and reduce congestion in the zone by at least 15%.

Mr Livingstone hailed the first day of his extended scheme a success.

"Today's morning rush hour has seen a successful start to the congestion charge western extension," he said.

"Traffic is flowing freely inside the extended zone, on its boundaries and the through route. The zone was, until now, one of the most congested areas in the UK and first indications are that traffic levels have been reduced as expected by the scheme."

However, the Centre for Economics and Business Research has estimated that the extension will lead to 6,000 job losses and £236m in lost business a year.

Campaigners say they have been ignored by the mayor and claim that two-thirds of residents oppose the new boundaries.

A "go-slow" protest was held on Saturday morning in a last-ditch attempt to stop the extension.

Organised by the West London Residents Association, the protest began at Addison Road, in Kensington, west London.

The convoy of about 50 cars - including a few luxury sports cars and the odd "Chelsea tractor" - then snaked its way along Earls Court Road, which will be the boundary of the new zone.

More than 55,000 residents in the new zone will receive a 90% discount on the fee - sparking a fear of more congestion.

Transport watchdog, London TravelWatch, believes that a two-zone system would have been better than one large congestion charge area.

TravelWatch chairman Brian Cooke, who supports the scheme, said: "The inclusion of more residents in the discount scheme will mean increased congestion in the existing zone, thereby lessening the benefits seen over the last few years from the congestion charge.

"We hope that the single zone arrangement will be reviewed by the Mayor when the operational contract comes up in 2009."

The AA said confused drivers who strayed into the zone would be penalised £100.

"As confused drivers wander in off the edges or from free through routes and get pursued for £100 fines by the bailiffs, the London congestion charge could become a monster," AA head of public affairs Paul Watters said.

"Such a beast only survives through punishing mistakes, with more than 30 per cent of income currently coming from penalty charge notices."

London Assembly Transport Committee chairmain Geoff Pope said the Mayor was using the wrong scheme in the wrong place.

"The clunky old camera-based system is inflexible and expensive to run, and the discount system for residents encourages people to use their cars all week. And, anyone can tell you that Kensington and Chelsea are hardly the worst areas for traffic," he said.

"There is a free north / south route through the zone, but navigating through Hyde Park Corner and Victoria without entering the zone will be a testing and stressful experience.

"The mayor should rather concentrate on targeting congestion hot spots by using tried and tested tag and beacon technology."

Simon Birkett, from the Campaign for Clean Air in London, said the western extension was a painful but necessary step by the mayor towards achieving World Health Organisation recommended standards of air quality throughout London.

"The mayor deserves some credit for taking the first steps in the United Kingdom to reduce air pollution by tackling congestion and traffic emissions," he said.

"Painful though it may be, road pricing and emission controls are necessary in London if the health and quality of life of those who live in, work in and visit London are to be protected."

TfL's director of congestion charging Malcolm Murray-Clark said the scheme had been operating for four years and was a proven success.

"Since the introduction of the charge in 2003, traffic levels have been reduced in the central zone by 20 per cent, meaning that each day in 2006 there were almost 70,000 fewer vehicles entering the charging zone compared to the number that had been entering each day before charging began," he said.

"Today the scheme has been extended to one of the most congested areas in the UK, in an effective and well-run process."

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