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Its extension to all of Greater London from 29 August has prompted a fierce backlash from many living in and around the newly encompassed areas, who face fines of up to 160 for each day they fail to pay. "They should be putting their energy and resources into bringing down air pollution, not a key anti-pollution measure," said Areeba Hamid of Greenpeace UK.
London's ULEZ mirrors similar low-emission zones to improve air quality in more than 200 cities in 10 countries across Europe. He has launched a scrappage scheme providing some funding to eligible vehicle owners. But critics say it does not go far enough.