Rishi Sunak has been accused of “shrinking and retreating” from global leadership as he used the Cop28 summit to claim that “climate politics is at breaking point” because of the costs of net zero. While many other world leaders, including King Charles, spoke of the urgency of action on the climate, the prime minister used his brief appearance at the summit in Dubai to promote his approach to slowing the pace of net zero policies and reducing pressures on family finances. Sunak said “not a single person” among world leaders at the summit had challenged him over a delay to banning petrol cars, after he switched to a more “pragmatic” approach to net zero targets several months ago. He said Britain was a leader on the climate and it was time for others to do more, saying other countries were “grateful” to the UK for what it had done so far. Sunak’s tone at the summit attracted criticism from charities, who accused him of “misreading the room”, while some Conservative politicians said he was risking the UK’s leadership position on the issue. Keir Starmer, the Labour leader, said Sunak’s words showed that the “smallness” of his politics was affecting his ability to show a “seriousness and a want to lead” on the climate. The prime minister’s messaging also stood in stark contrast to that of Charles, who gave the keynote speech. Noting that this was the hottest year on record, the king spoke of his worry that the pace of action was not quick enough, and told the summit: “Records are now being broken so often that we are perhaps becoming immune to what they are really telling us. We need to pause to process what this actually means: we are taking the natural world outside balanced norms and limits, and into dangerous, uncharted territory.” In a further embarrassment for Sunak, the monarch also wore a tie bearing the Greek flag throughout the day and for their meeting, at the end of a week in which the prime minister cancelled a meeting with his Greek counterpart over his request for the return of the Parthenon marbles. No 10 declined to comment, saying it was a matter for the palace, but Greek media interpreted the king’s move as tacit backing for Athens’ position. Sunak stayed just eight hours in Dubai and appeared irritated by questions about his commitment to climate goals, despite having watered down the UK’s targets, changed the definition of climate aid in order to meet his target of spending £11.6bn over five years, and committed to new oil and gas development in the North Sea. He claimed that the cost of the transition to net zero put public support for tackling the climate crisis at risk, and argued that what he called his pragmatism over the issue was not extreme or out of step with other countries. His speech to world leaders stressed that the UK was “totally committed to net zero”, but in a press conference he focused on urging other countries to be more ambitious, while saying the UK was “doing more than everyone else”. Referring to his delayed ban on petrol and diesel vehicles, he said: “Hand on heart, 100%, not a single leader that I have spoken to today has spoken about that. Do you know why? Because most of their targets are less ambitious than the UK’s.” He said the 2035 date for phasing out petrol and diesel cars was in line with other developed countries. He said it “demonstrates just how distorted this debate has become”, adding: “I shift a date to be in line with basically every other country, and it’s somehow portrayed as some extreme measure.” Starmer accused Sunak of “shrinking and retreating” from leadership on the global stage at Cop28. “For the prime minister to reduce this down in the way that he does, the smallness of his politics is becoming a feature of his politics,” he said. “We saw it with the Greek prime minister. We saw it with some of the lines that he was putting out about ‘eco-zealots’ as he got on the plane to come here. This is not something to shrink from, not something to retreat from.” Chris Skidmore, the Conservative former energy minister and adviser on net zero, told the Guardian it was “true the UK is a climate leader”, as it had led the G20 in halving emissions since 1990, been the first G7 country to commit to net zero and had the most ambitious nationally determined contribution of any nation. He went on: “But that doesn’t mean that we should stand still. As my mission zero review showed, net zero is the economic opportunity of the decade to deliver inward investment, regional growth, new jobs and greater exports, worth around £1tn by 2030. But if we aren’t prepared to lead any more, another country will take our place and reap the economic reward of leading the energy transition. “That’s what the US is attempting with its Inflation Reduction Act, or the EU with their green deal. We are at risk that by standing still, we will fall behind. There are no prizes for coming second, as there is no future economy without a green economy.” The former environment minister Zac Goldsmith, who resigned while accusing Sunak of being “uninterested” in green issues, was more critical, telling Sky News: “There’s no doubt our standing has diminished considerably in recent months. The UK is just not seen by our allies – big and also small island members of the Commonwealth – as a reliable or serious partner.” Charities and environmental campaigners were unimpressed by Sunak’s claims to be leading the world on the climate. Rebecca Newsom of Greenpeace UK said it was “an old hit we’ve heard one too many times”. “He masquerades like a headliner while reprising a sorry medley of net-zero policy rollbacks while keeping silent on the biggest issue that will make a difference to cutting emissions at this conference: a global phase-out of fossil fuels,” she said. “Compared with the hundreds of billions needed to support the poorest countries, the £1.6bn announced today barely touches the sides, and it’s clear that only around half of it is new money.” Tessa Khan, the executive director at Uplift, an organisation campaigning for a fossil fuel-free UK, said the prime minister had “completely misread the room”. “While the head of the UN implores countries to urgently phase out fossil fuels, the UK is one of just a handful of wealthy nations that is continuing to greenlight major new oilfields,” she said. “Rishi Sunak’s disinterest in tackling the climate crisis plays badly with voters at home, but to play dumb at Cop and ignore the UK’s role in literally adding fuel to the fire, for example by approving the massive Rosebank oilfield, is diplomatically embarrassing.”