Sadiq Khan refuses to role out further expansion of London's ULEZ zone
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Mayor of London Sadiq Khan refused to rule out further expanding London's pollution charge zone and told ITV News London policies may "need to be tweaked".
ULEZ has operated since April 2019, but previously only covered the same area of central London as the Congestion Charge.
It now includes all areas within the North and South Circular roads in an attempt to boost air quality.
Expanding that now to cover the whole of Greater London would have "taken too long" Mr Khan said, and he wasn't prepared to wait.
"The evidence from the experts is this expansion will lead to all of London seeing a reduction of 30% of nitrogen dioxide," Sadiq Khan said.
"If it's the case though that these policies need to be tweaked or refined then I won't be scared to do so," he added.
Whether or not a vehicle is liable for London’s charge depends on how much nitrogen dioxide (NO2) it emits.
NO2 damages lungs and can exacerbate existing conditions such as asthma, and lung and heart disease.
For diesel cars to avoid the charge they must generally have been first registered after September 2015, while most petrol models registered from 2005 are also exempt.
Transport for London said four out of five vehicles registered within the new, larger zone are compliant, but an estimated 130,000 are not.
The charge applies all day, every day, except on Christmas Day.
Drivers who fail to pay face being handed a Penalty Charge Notice of £160, reduced to £80 if paid within a fortnight.