Five EU countries have accused TfL of breaking the law by getting hold of the names and addresses of their citizens to send them the fines, with more than 320,000 penalties, some as high as thousands of euros, dished out since 2021.

Since Brexit, the UK has been barred from automatically getting EU residents' details. Transport bosses in Belgium, Spain, Germany and the Netherlands say that driver data can't be shared with the UK for enforcing London's ultra-low emission zone (Ulez), and claim the details were nicked by agents working for TfL's contractor Euro Parking Collection in one of the biggest personal data collection heists in history.

In France, more than 100 drivers have sued, saying their details were obtained by fraud, while Dutch truck drivers are taking TfL to court over £6.5 million of fines they say were unlawful.

According to Belgian MP Michael Freilich, who has looked into the issue for his voters, TfL is milking European drivers as a "cash cow" by using data obtained by cheating to issue unfair fines.

Freilich calls the situation "possibly one of the biggest privacy and data scandals in EU history."

Some drivers have even been slapped with fines of up to five-figure sums — for cars that met the rules but had not been registered.