A camera van used to police the Ulez expansion was slapped with a £110 fine after it appeared to be parked illegally.
The TfL enforcement vehicle received the ticket when it pulled up on the pavement in Cambridge Road, Kingston on Tuesday.
It was spotted by independent councillor James Giles, who immediately called in the borough's traffic wardens.
He told the Standard: "There are plenty of legal places to park in that area. It causes problems for people with mobility issues, but also damages our highway to have heavy vans parked on the pavement like that.
"I thought it was important to send a message that they are not above the law."
Motorists are not allowed to park on urban roads with their vehicle's wheels on pavements, grass verges or any land between carriageways.
A TfL spokesman said it would remind its drivers of their responsibilities and the contractor responsible will be paying the fine.
Mayor Sadiq Khan expanded the Ulez to the London boundary at the end of August in a bid to help clean up the city's toxic air.
It sees the drivers of older, more polluting cars face a £12.50-a-day charge.
The vans do not directly say they are policing the clean air zone, but have Transport for London markings as well as signs that they are carrying ANPR cameras.
Mr Giles added: "A lot of the Ulez cameras have been cut down in my ward in Kingston so we have seen a greater number of these vans around.
"While I don't agree with the Ulez expansion, I also don't agree with these 'blade runners' tearing the cameras down.
"If people want to oppose it then there is a democratic way to do so and that is at the Mayoral election next May."
The Met is currently investigating almost 800 cases of Ulez devices being defaced or stolen.
A TfL spokesman said: “TfL fully supports the use of highway authority powers to enforce against parking in unauthorised locations.
"We will remind drivers of their responsibilities and our contractor, who will be paying the penalty charge notice.”