A YouGov poll for City Hall found 65% of Londoners see a lot or a fair amount of climate disinformation online. Sadiq Khan cites the ULEZ row at COP31.

Sixty-five per cent of Londoners believe there is “a lot” or “a fair amount” of climate disinformation on social media, according to a YouGov poll for City Hall published on Thursday 12 November. The Mayor of London, Sadiq Khan, is taking the finding to COP31, the United Nations climate conference in Antalya, Türkiye, and is using the fight over the 2023 ULEZ expansion, the one that brought the charge to Bromley’s roads, as his main example.

YouGov surveyed 1,128 London residents aged 18 and over between 16 and 25 October 2026, weighted to represent all London adults, City Hall said.

Why Bromley drivers will recognise the argument

The Ultra Low Emission Zone now operates across all London boroughs, Bromley included, stopping at the M25. Drivers of vehicles that do not meet the emissions standards and are not exempt pay £12.50 a day, according to TfL.

Sadiq Khan says the campaign against that expansion was built partly on falsehoods. He is expected to tell world leaders: “London is no stranger to lies. When we expanded our clean air zone, now the largest in the world in 2023, we faced one of the most sophisticated disinformation campaigns ever seen. We overcame it and won. But evidence from all five continents shows London was just the canary in the coal mine.”

City Hall points to a 2023 investigation by the social media analysts Valent Projects, which identified around 3,700 apparently inauthentic accounts amplifying posts against the ULEZ expansion on X, then called Twitter. Valent estimated the operation cost at least £168,000 on X alone, based on the price of buying followers and automation software. The investigation did not establish who was behind it.

What City Hall says the ULEZ has done

The Mayor’s case rests on a study of children’s lungs. The Children’s Health in London and Luton (CHILL) study, led by Queen Mary University of London, funded by the National Institute for Health and Care Research and published in The Lancet Public Health, followed more than 3,400 primary school children in central London and Luton for five years after the original central London zone began in 2019.

Group Children with clinically impaired lung function, start End of study
Central London 14% 9%
Luton (comparison) 9% 7%

The study linked the cleaner air to faster lung growth in children. It looked at central London, not outer boroughs like Bromley, where the zone has only applied since the 2023 expansion.

City Hall also estimates, from a separate assessment, that roadside nitrogen dioxide in central London is 54 per cent lower than it would have been without the ULEZ and its expansions. Its other figures:

  • more than 3,000 zero-emission buses in London’s fleet, up since Sadiq Khan was first elected;
  • over 640,000 trees planted and 900 hectares of green space created or improved with Mayoral funding;
  • 193,700 tonnes of CO2 saved from new buildings between 2021 and 2025 by London Plan policies, which City Hall puts at the equivalent of 164,000 return flights from London to New York;
  • £54.9 billion in sales from London’s green economy in 2023 to 2024, with more than 20,000 businesses employing over 341,000 people, according to the London Low Carbon Market Snapshot 2025.

The speech

Sadiq Khan will be the first Mayor of London to speak at the World Leaders’ Summit at COP, City Hall says, addressing leaders from the main stage, a slot usually kept for heads of state and government. He is there as elected co-chair of the C40 network of global cities.

He is expected to say: “Climate disinformation is like a one-two punch to the planet and democracy. But here in Türkiye, we’re calling on the world to get its guard up to defend itself and mount a comeback, to deal a knockout blow to the dark forces distorting debate.”

And: “We often talk about climate action as if it were a question of sacrifice. But look at what we’ve delivered: health, happiness, and opportunity, not in some distant decade but right now.”

He will close with: “It’s time to resist the attacks and stand up for the facts, with a relentless focus on unlocking the finance and expertise we need to fund climate action and adaptation around the world. London and other great cities around the world are showing we can overcome this challenge, we can win this fight and we can create a fairer, greener, healthier and more prosperous planet for everyone.”

What it means for you

Nothing changes on the road: the ULEZ charge in Bromley stays at £12.50 a day for non-compliant vehicles, and the standards and exemptions are on TfL’s ULEZ page. Yesterday the Mayor took City Hall’s heatwave cost figures to the same conference.

The poll and figures come from the Mayor of London’s press office.