Heathrow Airport’s controversial plans to build a third runway have been thrown into doubt after a court ruling.
The government’s Heathrow’s expansion decision was unlawful because it did not take climate commitments into account, the Court of Appeal said.
Heathrow said it would challenge the decision, but the government has not lodged an appeal.
The judges said that in future, a third runway could go ahead, as long as it fits with the UK’s climate policy.
The case was brought by environmental groups, councils and the Mayor of London.
The Court of Appeal found that the government had not followed UK policy when backing the controversial expansion plans.
It said that the government had a duty to take into account the Paris climate agreement, which seeks to limit global warming.
It was “legally fatal” to the government’s Heathrow expansion policy that it did not take those climate commitments into account, the judges said.
One of the environmental groups which brought the case, Greenpeace, said the government needed to “permanently ground Heathrow’s expansion plans”.
This judgement will fly round the globe quicker than a 747.
More and more politicians worldwide are pledging to make their economies climate neutral, but the Appeal Court judges have shown exactly what this intention implies.
From now on, every infrastructure spending decision in the UK could face legal challenge if it doesn’t comply with the Climate Change Act, which mandates virtually zero emissions by 2050.
It’s not clear that’s what MPs intended when they signed up to the 2050 target, but in today’s court ruling, it’s what they’ve got.
The prime minister’s decision not to appeal against the ruling may also call into question aviation expansion in other airports, as there is currently no viable technical fix to make planes zero-carbon and carbon offsetting schemes proposed by the aviation industry are contentious.
Environmentalists see today as the day the reality of climate change finally dawned.
Greenpeace UK’s executive director, John Sauven, said: “The third runway is already on its knees over costs, noise, air pollution, habitat loss and lack of access, and now Heathrow Ltd has yet another impossibly high hurdle to clear.
“No amount of spin from Heathrow’s PR machine can obscure the carbon logic of a new runway. Their plans would pollute as much as a small country. Boris Johnson should now put Heathrow out of its misery and cancel the third runway once and for all. No ifs, no buts, no lies, no U-turns.”
But the British Chambers of Commerce (BCC) said business communities in the UK would be “bitterly disappointed that plans for a world-leading hub airport are now at risk”.
“Without expansion, firms risk losing crucial regional connectivity and access to key markets across the world,” said BCC director general Adam Marshall.
Airline group IAG, which owns British Airways, said: “We have always said the environmental impact and cost of Heathrow expansion needs independent review. The airport cannot be trusted. Its original £14bn cost for expansion is now £32bn.”