Drivers of vehicles with the highest greenhouse gas emissions, such as sports utility vehicles and high-powered performance cars, will pay a daily charge of 25 pounds (S$69.08) to drive into central London.

Meanwhile those with the lowest carbon dioxide emissions will receive a 100 per cent discount on the congestion charge.

Drivers already have to pay an eight-pound charge to enter central London, a measure aimed act cutting traffic congestion.

The plans would be introduced on October 27, providing Livingstone gets re-elected in May for a third four-year term.

'I believe this ground-breaking initiative will have an impact throughout the world with other cities following suit as they step up their efforts to halt the slide towards catastrophic climate change,' he told reporters.

'I think the scheme will start a cultural revolution whereby drivers in every city in Britain start to think about the impact on the environment of their choice of car and how they plan their journeys.'

Mr Livingstone hopes the scheme will raise 30-50 million pounds per year, which will largely be ploughed into improving cycle routes in London.

Of the cars currently driving in the congestion charge zone, 17 percent would be liable for the 25-pound charge, while just two per cent would not have to pay anything.

Mr Livingstone said he had every sympathy with Scottish hillfarmers who needed four-wheel drive vehicles but said it was ludicrous for Londoners to drive them around city streets. -- AFP