Rishi Sunak has been accused of showing disregard for the climate crisis after Whitehall officials warned that some of his key green pledges were already unachievable. With the prime minister facing a backlash within his own party after appearing to row back from his commitment to green policies, an internal government audit found that a series of measures designed to help meet Britain’s net zero goals had been allowed to run off course. A scheme to reduce packaging, a deposit return plan for plastic bottles, a boost for recycling and a tree planting and woodland creation programme have all been given a “red” rating by Whitehall’s major projects body. It concluded that their successful delivery “appears unachievable”. The revelation backed up claims that the government is in “full and chaotic retreat” on climate pledges. Sunak has already signalled that the UK’s net zero targets should not “unnecessarily give people more hassle” and on Saturday announced that he had ordered a review of the rollout of low-traffic neighbourhoods, telling the Telegraph he was “on the side” of motorists. Meanwhile, Grant Shapps, the energy secretary, has said the government will “max out” the remaining oil and gas reserves in the North Sea. And levelling up secretary Michael Gove has called for a review of the phasing out of gas boilers by 2035. Sunak is preparing to use the coming week to herald the government’s “energy security” plans, including support for the oil and gas industry. Green campaigners fear the government will soon approve the controversial Rosebank oilfield in the North Sea, although Whitehall insiders denied the announcement would be made this week. Senior Tories are preparing to speak out should approval be granted. It is a sign the Tory leadership is willing to use green policies as a weapon against Labour. The shadow climate change secretary, Ed Miliband, has accused the Conservatives of “deepening climate disaster” by planning to stay on fossil fuels “as long as possible”. Writing online for the Observer, he said this is a “recipe for higher bills”. “The Tories have decided to double down on their disastrous mistakes – lurching desperately towards a culture war on climate, seeking to upend the climate consensus of the last 15 years,” he says. “This will not work; as poll after poll reiterates, the vast majority of the British people, in towns and cities across the country, are united in their desire for action.” After a week that saw scientists use heatwaves across Europe and the US as evidence of a human-caused climate crisis, the newly appointed head of the UN body that tracks climate science said governments needed to implement green plans that protected the disadvantaged. Prof Jim Skea, elected last week as the new head of the Intergovernmental Panel on Climate Change (IPCC), told the Observer that leaders needed to oversee a “just transition” to ensure pro-climate measures retained public support. “We need to be very aware that the ambition of the climate action we need to take really does have social and economic consequences,” he said. “It’s very important that we are very clear about what these implications are and that we are also very clear about the way that the costs will fall on different groups in society. “We need to keep talking to people to explain what’s going on, explain what the choices are, and explore ways of minimising the effects of the measures themselves on disadvantaged people. It’s really, really important because frankly, unless we address these issues, we will not be able to take people with us and we won’t get the action that is so very clearly needed. Climate action will touch people’s lives. That, I think, is the biggest challenge.” Concerns over the government’s commitment to green policies have been raised by findings by the Infrastructure and Projects Authority (IPA), which monitors the progress of major schemes. The IPA has given a red rating to several schemes that contribute to Britain’s net zero pledges. Any schemes placed in the red category are regarded as having “major issues with project definition, schedule, budget, quality and/or benefits delivery, which at this stage do not appear to be manageable or resolvable”. It includes policies that fall under a programme aimed at reducing packaging and boosting recycling. Just last week, ministers delayed one of the schemes – the “extended producer responsibility” programme, designed to make companies pay for the collection, recycling and disposal of packaging waste. The Nature for Climate Fund, established to increase tree planting and the restoration of peatlands to support the transition to net zero, was downgraded from amber to red by the IPA. MPs recently reported that the government had met less than half of its annual tree-planting target in England. Wera Hobhouse, the Liberal Democrat climate spokesperson said: “The fight against climate change is a race against the clock, so there’s no time for sluggish progress. Yet the current Conservative approach involves kicking the can down the road and failing to deliver on key environmental projects. This latest damning report adds to the Conservative party’s shameful track record on the climate.” Greenpeace UK said: “In the fight against climate breakdown, plastic pollution and the destruction of nature, our government is in full and chaotic retreat. The real winners from rolling back green policies are the fossil fuel companies and big plastic producers who can carry on making a tidy profit at the expense of climate and nature.” The Department for Environment, Food and Rural Affairs said it had delayed packaging reforms to give industry, local authorities and waste management companies more time to prepare. It said it was committed to introducing a deposit return scheme for drinks containers. “We can be proud of the UK’s record as a world leader on net zero,” said a spokesperson. “We are going far beyond other countries in reducing emissions, eliminating avoidable waste, and restoring nature. We are engaging closely with the partners to deliver these projects while our Nature for Climate Fund has supported the planting of 13m trees and the restoration of thousands of hectares of peatland.”