Motorists could be charged based on how many miles they drive in London, if a think tank gets its way.

The Centre for London has urged Sadiq Khan to consider the measure as a way of reducing air pollution and making money for Transport for London.

Claire Harding, research director at the Centre for London, spoke out after a City Hall study found Black and Asian residents are more likely to suffer the effects of poor air quality.

“We know that Londoners living in the most deprived areas of the city are exposed to around a quarter more NO2 pollution than those living in the wealthiest areas,” she said. “Air quality is a matter of equity.”

The research found nitrogen dioxide levels were 13 per cent higher in the most deprived areas of London compared to the wealthiest.

Claire praised the expansion of the Ultra Low Emission Zone but said "greater action" is needed to reduce emissions and inequality.

“Transport for London should go further,” she added.

“They should adopt a pay-per-mile road user charging scheme which would deliver cleaner air, increase walking and cycling, and reduce congestion, as well as provide a substantial income stream to help plug TfL’s finances.”

Mr Khan is also said to be considering a "boundary tax", which would see drivers pay a levy for entering the capital from the outside. TfL is said to be exploring new ways to balance its books after being hit by under usage during the lockdown.

Transport for London has been approached for comment.