UK absent from key international statement on climate action

The UK was notable by its absence on Wednesday from a key statement pledging ambitious action on the climate crisis, from a group of countries of which it is normally a leading member.

The “high ambition coalition” of countries, which aims to push the world to swifter cuts on greenhouse gas emissions, issued a call for “faster stronger” action on the climate, to cause emissions to peak by 2025, and a plan to put the world on course to meet the goals of the 2015 Paris agreement.

The UK, which was a founding member of the coalition, was not among the 17 signatories, which included France, Spain, Kenya and Chile. Nor was Rishi Sunak in attendance in New York, when the UN secretary general, António Guterres, welcomed global and civic leaders to discuss the crisis at his climate ambition summit, opening on Wednesday on the sidelines of the UN general assembly.

Instead, the prime minister was hatching a U-turn on the climate with a scope and timing that has left other countries and green experts aghast. Downing Street trailed on Tuesday evening proposals, expected to be unveiled on Friday, to water down key measures on net zero, including pushing back the ban on new diesel and petrol cars, and on new gas boilers.

Related: Senior Tories express unease over Sunak’s intention to roll back climate policies

Sadiq Khan, the mayor of London, was the only UK leader speaking at the UN climate ambition summit in New York. He told the Guardian: “We’re in a climate emergency. The deadly impacts of climate change are here now and we have to act urgently. We have seen record high temperatures in London earlier this month and the hottest ever July. Over the last two years we have experienced unprecedented wildfires and flash floods – destroying homes and livelihoods.

“This government’s response flies in the face of common sense and shows they are climate delayers. It beggars belief that not only are they watering down vital commitments, but they are also passing up the opportunity to create green jobs, wealth and lower energy bills – as well as failing to give investors the certainty they need to boost the green economy.”

Sunak announced earlier this month that he would not attend the UN general assembly, as he was too busy. But the Guardian subsequently revealed that if he had gone, he risked being barred from speaking at the climate ambition summit, because only countries that could demonstrate they were implementing stringent emissions plans would be allowed.

Many saw a significance in the timing of Sunak’s expected change of stance. “This is headline management by Sunak,” said Tom Burke, a veteran government adviser and co-founder of the E3G thinktank. “It’s about provoking outrage, maybe protests. The timing of this is to change the story about Sunak not having been invited to the climate ambition summit. The real cost of this is to delay investment in absolutely everything to do with energy as companies wait for this government to be gone. Incoherence is too generous a description but I can’t find a more accurate word even with the help of a thesaurus.”

Helen Clarkson, the chief executive of the Climate Group, which organised Climate Week New York, said: “UK climate leadership is crumbling around us. That the prime minister has chosen Climate Week NYC to water down the policies needed to meet our legally binding climate commitments is beyond me. What planet is he on?”

Developing country campaigners were also dismayed. Mohamed Adow, the director of the Kenyan thinktank Power Shift Africa, said: “This action from Sunak is a disgusting betrayal of vulnerable people around the world, not to mention economic vandalism upon his own country. The climate crisis was birthed in the UK through its creation of the combustion engine.

“Through its commitment to these net zero policies, the UK had been doing its part in ending the climate crisis. Yet Sunak will set all that on fire if he tries to reverse these policies. [He] is an ignorant politician who shows contempt for vulnerable people and the future of the planet.”

The UK’s international reputation for leadership on the climate crisis, burnished by hosting the Cop26 UN climate summit in Glasgow in 2021, was also in danger, several prominent climate experts said.

Rachel Kyte, dean emerita of the Fletcher School at Tufts University in the US, and a former UN climate envoy, said: “If Prime Minister Sunak – in London, avoiding the global stage – does start watering down UK climate policies he is doing so against advice, and out of sync with the international consensus. Making net zero a scapegoat for years of the government mismanaging the economy and energy policy is a dangerous stunt.”