The Green Party leader of Bristol City Council flew 3,500 miles to the US for a climate change event only five days after the local authority banned flight adverts.

Tony Dyer joined New York mayor Zohran Mamdani at the Urban20 Mayors Summit in Manhattan on Sunday, which saw dozens of representatives speak about Net Zero action.

Mr Dyer was pictured in discussions with Mr Mamdani and in another photo sitting with fellow local leaders enjoying a tour on an open-top sightseeing bus.

He was in America to represent Bristol and other UK 'Core Cities' – including Leeds, Manchester, Birmingham and Liverpool – in his role as Net Zero lead for the group.

But it came after councillors in Bristol voted on September 15 to ban ads for 'polluting' and 'high carbon' industries such as flights, non-electric cars and fast fashion.

The prohibition – also covering cruises, travel agents and even Black Friday deals – was made on the basis that such products could harm people or the environment.

The authority is Britain's first to bring in such a ban, which is being enforced on council-owned roadside billboards, street digital screens and bus shelters.

Tory deputy chairman Matt Vickers said the Greens were 'perfectly happy to lecture working families about their carbon footprint while their own leaders rack up airmiles'.

He told the Telegraph: 'Conservatives trust people to decide for themselves whether to get on a plane, and we would have councils spend their time emptying the bins and fixing the roads rather than policing billboards.'

Mr Dyer has defended his trip to New York, claiming his attendance at the meeting ensured that he could put across the perspectives of Bristol and other UK cities.

He said in a statement: 'Every journey undertaken by officers or councillors is assessed not only for value to taxpayers, but also for its environmental impact. There are occasions, however, when being present in the room matters.

'The opportunity to influence international discussions, strengthen partnerships, share learning and attract future investment cannot always be replicated remotely.

'Of course, attending international events raises legitimate questions about travel and carbon emissions, particularly for those of us committed to climate action. I believe it is important to be transparent about that.'

Mr Dyer insisted that his trip was only the third time he had taken an international flight since becoming council leader in May 2024.

He added: 'We have a particular focus on cutting long-haul flights and considering lower-carbon alternatives wherever possible. Since I became leader of Bristol City Council, the organisation has significantly reduced emissions from air travel.'

Mr Dyer said data from his first 18 months in office showed total flight emissions were down 28 per cent, and flight emissions from politicians' travel had fallen 64 per cent.

The money for Mr Dyer's return flights to New York and hotel stay has come from council funds – but the total bill has not yet been revealed, reported Bristol Live.

Last week, the council's deputy leader Heather Mack welcomed the marketing ban, saying advertising 'forces itself upon all of us', adding: 'It has negative impacts on our health and wellbeing, as well as the climate, environment and local economy.'

Council officers said it could cost Bristol £80,000 a year in lost income – but similar projected losses from a ban on junk food adverts five years ago did not materialise.

Green Party leader Zack Polanski rejected an invitation to meet Mr Mamdani after his election as New York City mayor last November because he refuses to fly.

The party has previously revealed plans to tax frequent flyers and ban domestic flights for journeys that would take less than three hours by train.

In 2022, Bristol's then-mayor Marvin Rees courted controversy by flying for nine hours to attend a conference in Vancouver, Canada, and talk about climate change.

He later defended his travel for the 14-minute TEDx lecture, saying virtual attendance 'wasn't on the table' and adding: 'Have you seen any Ted conferences run by Zoom?'