They are reported to be part of the group Action Against ULEZ with some protestors carrying signs branding the mayor a “liar” while others described the ULEZ cameras as “scameras” designed to entrap drivers.
It is the latest step in the anti-ULEZ campaign which has seen some opponents of the scheme illegally target the cameras used to enforce it.
The scheme was expanded in August bringing five million more Londoners into the clean air zone and prompting a fresh war of words between campaigners and critics of the scheme.
It was hailed by the mayor as the “biggest, strongest ultra-low emission zone” of its type in the world, but opponents argued it will put a further financial burden on the poorest during a cost-of-living crisis as drivers with older vehicles in outer boroughs now face a £12.50 daily charge.
Its widening became a deeply political issue this year and it was blamed for Labour’s failure to win the Uxbridge and South Ruislip parliamentary by-election in July.
That defeat pushed the issue to the top of the political agenda with Prime Minister Rishi Sunak pledging to crack down on “anti-motorist” policies.
Earlier this month the Prime Minister delayed the ban on the sale of new conventionally fuelled cars and vans from 2030 to 2035 and he has criticised local authorities for bringing in lower speed limits.