The UK must act urgently to meet its international climate commitments, the independent climate watchdog has warned, after sending “mixed messages” to other countries at the Cop28 UN climate summit in December. While carbon reduction from electricity generation has shown progress, the rate at which all other sources of emissions are being cut must quadruple to meet the UK’s target under the Paris agreement of 68% reductions in emissions by 2030, according to the Climate Change Committee. Piers Forster, the interim chair of the committee, said: “We must rapidly replace fossil fuels with low-carbon alternatives to get back on track to meet our 2030 goal. The UK could set a powerful example of tackling climate change and reducing our insecurity to climate impacts.” The committee released its summary of the implications of the Cop28 outcome for the UK on Tuesday. At the summit, nations agreed for the first time to target a transition away from fossil fuels, although the framing of the commitment was weaker than many nations hoped. The UK was sharply criticised by civil society leaders, and privately by many countries, for its stance at the summit. Rishi Sunak, the prime minister, attended only briefly and held few meetings with his counterparts, while his U-turn on net zero only weeks before cast a shadow over British participation in the talks. In measured language, the CCC, which advises the UK and devolved governments on emissions targets, said the government had “maintained a strong presence at Cop28”, but added: “The international perception of the UK’s climate ambition suffered from mixed messages following announcements on new fossil fuel developments and the prime minister’s speech to soften some net zero policies. The committee urges a continued visible presence at future Cops and even greater domestic climate ambition to reinforce the UK’s international standing.” In September, Sunak rowed back on key climate policies, including postponing the phase-out of sales of new fossil fuel vehicles, and announced fresh licences for North Sea oil and gas, which were greeted with international dismay. At Cop28, the UK argued for the phase-out of fossil fuels, but at home Sunak was insisting that oil and gas would have a central role in UK energy for decades. The government also gave the green light to a new coalmine, while other countries were being urged to give up coal. Rebecca Newsom, the head of politics at Greenpeace UK, said: “The UK government wears its hypocrisy on its sleeve when it comes to climate policy, and this new report from the CCC really spells it out. Our climate is on a knife-edge, and there must be no more empty words or hollow promises. The government must immediately end new oil and gas production and tax fossil fuel companies more to generate new public finance for climate action both at home and abroad. Only then can the UK begin to credibly claim it is a global climate leader.” Carla Denyer, co-leader of the Green party, said: “Through its drive to ‘max out’ on North Sea fossil fuels, the UK government has blown any pretence of global leadership on tackling the climate crisis. We need to call time on all new licences for fossil fuel exploration, accelerate the move towards renewable energy and implement a large scale home insulation programme. That is how the UK can show climate leadership.” At Cop28, after two weeks of tense negotiations, countries agreed to “transitioning away from fossil fuels in energy systems, in a just, orderly and equitable manner”. This was the first time that a conference of the parties under the UN Framework Convention on Climate Change had made a major commitment explicitly referring to fossil fuels. However, it gave no timeframe for the move away from fossil fuels and no details on how it would be achieved, while the term “energy systems” was judged ambiguous by some. Cop28 was held in the United Arab Emirates, one of the world’s biggest oil and gas producers. This year’s Cop29 will be held in Azerbaijan, for which oil and gas production are the mainstay of the economy. Activists and many countries are concerned that there may be backsliding from fossil fuel producers at the talks, seeking the loosest possible interpretation of the commitments made at Cop28. A UK government spokesperson said: “We welcome the Climate Change Committee’s recognition of the UK’s pivotal role at Cop28 and our strength in climate diplomacy. The UK is leading international action, delivering an agreement to transition away from fossil fuels and as one of the largest contributors to the loss and damage fund.” They added: “We are the first major economy to halve our emissions, have some of the world’s most ambitious legally binding targets, and have over-delivered on every carbon budget to date, while our significant investment in the UK’s world leading clean energy sector – with 40% of our electricity now renewable compared to just 7% in 2010 – is bolstering our energy security.”