London needs to charge motorists by the mile to hit climate change targets, according to Mayor Sadiq Khan.
He wants road pricing to be implemented to encourage people who drive petrol or diesel cars in the capital to switch to public transport, walking, cycling or electric vehicles “where necessary”.
The Labour mayor said he is “not willing to put off action”.
Research commissioned by Mr Khan found that a 27% reduction in London’s car traffic is required by 2030 to meet net-zero ambitions.
London faces severe impacts of climate change, with an increase in extremes such as the flash floods last summer which closed hospitals, hit Tube stations and flooded homes and businesses, as well as deadly heatwaves, a report by City Hall warned.
The city must play its part in tackling the global crisis, the document stated.
Road user charging would be a “simple and fair scheme” that could replace existing fees such as the Congestion Charge and Ultra Low Emission Zone (Ulez), according to the report.
But making people pay based on how far they drive has often been viewed as politically toxic.
Consideration of such a scheme has not been government policy since the then-Labour administration abandoned proposals in 2007 after an online petition attracted 1.8 million signatures.
The City Hall document noted that the technology to charge drivers per mile is “still years away from being ready”, so Mr Khan is considering several policies which “could be ready within the next few years”.
One approach is for the Ulez to be extended beyond the North and South Circular Roads to cover the whole of London.
Existing charge levels and emissions standards could be maintained, or a “small” fee could be charged for “all but the cleanest vehicles”.
Mr Khan is also considering charging drivers of vehicles registered outside London for entering the capital.
The Mayor and Transport for London will conduct a public consultation on the proposals.
Mr Khan said he wants “an earnest conversation with Londoners”.
The chosen measure could be implemented by May 2024.
Mr Khan said he is “not willing to stand by and wait when there’s more we can do in London that could make a big difference”.
He went on: “We have too often seen measures to tackle air pollution and the climate emergency delayed around the world because it’s viewed as being too hard or politically inconvenient, but I’m not willing to put off action we have the ability to implement here in London.
“I’m determined that we continue to be doers, not delayers – not only to protect Londoners’ health right now, but for the sake of future generations to come.”
AA president Edmund King said simply “charging vehicles off the road” is not the solution to cutting pollution.
“We need to encourage the uptake of cleaner, greener vehicles,” he added.
Consultancy Element Energy was commissioned by the mayor to set out scenarios for cutting London’s carbon emissions to zero overall – known as net zero.
The most ambitious scenario, Mr Khan’s preferred option, could require £75 billion investment between now and 2030 in infrastructure, and more beyond, from public and private sources, according to the mayor.
Hitting the target will require 2.2 million heat pumps in operation by the end of the decade, more solar panels on roofs, and bringing in heat networks for heating homes.
And there will need to be a nearly 40% reduction in total heat demand of buildings – which will mean more than 200,000 homes a year need to be retrofitted with measures such as insulation to stop heat leaking out of them.
Mr Khan has warned he does not have the funding or powers to deliver everything required, and wants the Government to provide greater support.