The government is under growing pressure to halt a proposed expansion of Leeds Bradford airport, which critics say would wreck efforts to tackle the ecological crisis and undermine the government’s credibility ahead of a key climate conference later this year. The expansion plans, which would support an increase in passengers from 4 to 7 million people a year by 2030, were given conditional approval by Leeds city council earlier this month despite widespread opposition from local MPs, residents and environmental groups. Now the same lawyers who are taking on the government over a proposed new coalmine in Cumbria have written to the secretary of state for housing, communities and local government, Robert Jenrick, on behalf of campaigners asking him to “call in” the decision. “[The] expansion would commit the UK to decades of increased carbon emissions, against the Climate Change Committee’s advice,” said barrister Estelle Dehon, who is acting on behalf of the Group for Action on Leeds Bradford Airport (Galba). “As with the proposed Cumbrian coalmine, allowing this in the year we host Cop26 undermines the UK’s ambition to lead on the climate crisis.” Dehon said the “call-in” process would allow the national and international ramifications of granting permission for both the airport to be considered. Supporters of the project say the airport expansion would boost the local economy by hundreds of millions of pounds and support thousands of new jobs. However, critics dispute the figures and say it would lock the region into a diminishing carbon intensive economic future. A report from the New Economics Foundation, commissioned by campaigners, found that there would be little if any economic benefit, adding that if the impact of more people holidaying abroad rather than in the UK was factored in, the expansion would actually be a drain on the economy. Leeds Bradford is one of several airports – including Stansted, Southampton and Bristol – that are attempting to get backing for expansion proposals in the coming months. A spokesperson for Leeds Bradford airport said the planned increase in passengers at the airport was not dependent on the expansion, but would ensure it was able to “deliver the level of passenger experience it aspires to”. They added: “We are pleased with the support for a replacement terminal and the recognition by Leeds city council that our proposals are compliant with local, national ​planning policy and​ national aviation policy.” Leeds city council said it had looked at all aspects of the plans, adding: “Current government policy points to these emissions being something that should be primarily tackled at a national level – and addressed through international agreements and protocols – rather than by suppressing growth at individual airports in a way that could simply export passengers to other nearby airports at a higher financial cost to them and increase surface transport emissions.” But green groups say the government must get a grip on high carbon infrastructure schemes – being given the go-ahead by local councils – if it is to have any credibility in the fight against climate breakdown. Ariana Densham from Greenpeace said: “From new coalmines to expanding airports, the government has a deeply concerning, but growing habit of recklessly passing the buck on the signoff of polluting mega-projects. These are local decisions that will have global consequences.” The scheme has also been criticised by local MPs, five of whom signed a letter alongside councillors, environmental groups and climate scientists calling for the plans to be scrapped. “Expansion would mean health damaging increases in noise, traffic and air pollution for thousands of people in our local communities,” it stated.” Above all, it would mean a huge increase in greenhouse gas emissions exactly when we need to cut them to prevent the worst effects of the climate crisis.” A spokesperson for the Department for Local Communities and Government said that because of the scale of the proposed development and its green belt location the application, if given final approval by the council, “will be referred to the secretary of state”. However, Dehon said this did not answer campaigners’ climate concerns. “[The government’s] response has been to put off any decision about call-in, because at some future point the council is obliged to refer the green belt impact to Mr Jenrick so he can consider call-in on that basis. This delay is unjustified. And green belt referral is no guarantee that the decision will be called in.”