Dozens of humanitarian charities and green groups have written to Boris Johnson in protest at government approval for a new UK coalmine.
They warn the decision is “an embarrassment” when Britain is hosting international talks this year, when other countries will be urged to set tougher climate goals.
And they are calling on the prime minister to send the decision to a public inquiry, saying backtracking would “help restore confidence in the UK government’s climate leadership, both internationally and at home”.
Exactly a year ago, Mr Johnson announced the deadline for the phase-out of coal from Britain’s energy system would be brought forward a year to 2024, under a government drive to reach net-zero carbon emissions.
But earlier this month Robert Jenrick, the local government secretary, refused to block a 2019 decision by Cumbria county councillors to give the green light to the UK’s first deep coal mine in 30 years.
This was despite pleas for Mr Jenrick to intervene, and despite government pledges to rapidly decarbonise the economy.
The mine would take coal from under the Irish Sea to make steel, and supporters say less coal would have to be imported.
The government defended its decision, saying the planning approval was a local matter.
However, the prime minister’s father, Stanley, told the BBC the decision was a “massive mistake” in public-relations terms.
“How can we ask other countries to bring in their climate change-reduction programmes when we are reopening the whole argument here in Britain?” he asked.
The 81 people who signed the letter include representatives of Oxfam, Save the Children, the RSPB, the New Economics Foundation, Friends of the Earth, the Wildlife Trusts, Greenpeace and Christian Aid.
In 2017 the UK co-founded and now co-chairs the PoweringPast Coal Alliance, a group of governments, businesses and organisations that push for a switch from coal power generation to clean energy.
The letter – seen by The Independent – says given that the UK’s credibility is at stake, it is “mystifying” that the government is not intervening.
“This decision will make it much harder to fulfil the ambitions of the Powering Past Coal Alliance,” it warns. “Alok Sharma MP, the COP president, when questioned before a Commons business select committee,clearly understood that the mine approval was an embarrassment.
“The Climate Change Committee has urged the government to reconsider, highlighting that the increase in emissions from this mine alone would amount to more emissions than it has projected for all open UK coal minesto 2050.”
Mike Starkie, mayor of Copeland council, told the BBC the mine would bring large numbers of jobs and prosperity to the area. “It’s been broadly welcomed across Copeland – I’ve never known a project that’s carried so much public support,” he said.
The signatories acknowledge it is “crucial” to support West Cumbria in switching to sustainable employment but claim research shows that investment in green industries locally would provide significantly more than the mine’s 500 jobs.
The Climate Change Committee says all coal, including coking coal, should be phased out by 2035, they point out.
“The government therefore risks allowing the creation of a stranded asset as the mine may be required to close only a few years after it opens.
“It also sends the wrong signal to all those countries who want to hold on to coal, from Poland to China.”
Friends of the Earth coal campaigner Tony Bosworth said: “The mounting criticism over the government’s coal mine decision is completely justified. This new mine undermines Boris Johnson’s credibility ahead of this year’s crucial climate summit.”
The Independent has asked the government to respond.