Transport for London (TfL) is pursuing legal action potentially worth up to £1bn against carmakers including Stellantis, Jaguar Land Rover, BMW and Nissan, alleging fraud and negligence over diesel vehicles that avoided paying to enter the capital's ultra-low emission zone (Ulez). TfL's lawyers argue manufacturers falsely represented that certain diesel models met emissions standards, allowing them to enter the zone without paying the daily charge and depriving TfL of revenue while undermining efforts to improve air quality.

The Ulez, launched in 2019 and expanded citywide in 2024, charges owners of the most polluting vehicles, mostly diesels over 11 years old, £12.50 a day. TfL's case, launched in 2024, was paused pending the separate "dieselgate" litigation over alleged defeat devices, which was largely rejected by the High Court this month, though an appeal is being considered; TfL has now been granted a stay until October while that appeal is weighed. Lawyers for the manufacturers say TfL's allegations are serious but lack proper detail, while TfL says the case concerns lost Ulez revenue and remains central to its air quality goals.