The mayor of London suggested Friday that a road-fee program targeting polluting cars in the city could be expanded to cover the entire metropolitan region of the British capital.

In April 2019, the London Assembly enacted an ultra-low emission zone (ULEZ), requiring owners of polluting vehicles to pay £12.50 ($17.20) per day to drive in the city center.

Last year, this zone was expanded to include a much larger area between the northern and southern orbital highways, which is home to over four million people.

On Friday, Sadiq Khan announced that he had asked Transport for London to consult on expanding the ULEZ scheme throughout the entire city in 2023 "to make London a greener, healthier, and less congested city."

The population of Greater London is around nine million people.

"The triple challenges of tackling toxic air pollution, the climate emergency, and congestion mean we need to further reduce emissions from vehicles in London," said Khan.

"We simply don't have time to waste. There is still far too much toxic air pollution permanently damaging the lungs of young Londoners and leading to thousands of deaths every year, with the greatest number of deaths attributable to air pollution in outer London boroughs."

"In weighing up the different options, the rising cost of living was a key consideration for me... I'm not willing to ask people to pay more unless I'm absolutely convinced it's justified to save lives," he added.

Pollution damages, solution 

The extension, according to Khan's office, will cut nitrogen dioxide emissions by 285 to 330 tonnes, carbon dioxide emissions by 135,000-150,000 tonnes, and the number of "most polluting cars on London's roads" by 20,000 to 40,000 each day.

Air pollution caused around 1,000 annual hospital admissions for asthma and serious lung conditions in London between 2014 and 2016, according to a 2019 report.

In 2020, a coroner ruled that air pollution made a "material contribution" to the death of a nine-year-old child in 2013. 

Some argued that the earlier ULEZ extension was a "tax" on poorer drivers who couldn't afford to replace their polluting vehicles and that it would hurt small companies.

Cars, motorcycles, smaller vans, and minibusses will be charged based on their declared emissions.

Those who drive a vehicle in the city center at the busiest times also have to pay a congestion charge of £15, a measure first introduced in 2003.