As the UK prepares to host the next round of major global climate talks in November, Prime Minister Boris Johnson’s government has adopted the most ambitious emissions-reduction goal among large economies.

It’s hoping that leading by example will encourage other countries to put forth stronger targets to arrest global warming. That’s why the UK government’s backing of a new coal mine has baffled climate experts. Endorsing the extraction and use of the dirtiest fossil fuel directly contradicts its green agenda.

“It’s a disastrous decision for the UK’s claim to climate leadership,” said Rebecca Willis, a professor at the Lancaster Environment Centre. “It’s confusing to people that, as the country leading international climate negotiations, the UK is telling other countries what it expects of them, but consenting to a new development digging out the most polluting fossil fuel.”

The UK government’s own adviser on these issues, the Climate Change Committee, declared last week that the decision to open up a new coal mine “gives a negative impression of the UK’s climate priorities.”

The Johnson administration’s difficult position echoes a bigger conundrum. Many countries are trying to balance their desire to contribute to the global fight against climate change against domestic pressures to exploit their own natural resources. The UK government’s defense of the new mine is a good case study of the doublespeak rife in climate diplomacy.

First, the facts. The new mine, located in the West Cumbria region, is expected to receive permission to keep digging till 2049—just one year before the UK’s legally mandated deadline to reach net-zero greenhouse gas emissions. The country will use some of the coal for making steel, but 85% of it is marked for export to Europe.

In that period, the CCC expects the project to add about 400 000 metric tons of carbon dioxide equivalent of emissions each year. Willis’ analysis, which accounts for all emissions from burning the coal from the mine, whether added to the UK’s ledger or not, comes to a staggering 420 million tons. That’s approximately how much the UK emitted from all its activities in 2018.

In West Cumbria, about 25% of the population has no educational qualifications and about 25% of the population is above the age of 65. The prospect of 500 jobs at the new mine convinced the local council to approve it. But it also defended the decision by saying that opening the coal mine at home saves another country from opening a mine to meet the U.K.’s demand, while saving emissions from transporting that coal.

Such arguments are “economic nonsense,” Paul Ekins, professor of resources and environmental policy at University College London, wrote in April. The increase in supply of a commodity (in this case, coal) reduces its price, which could encourage greater use and thus increase demand and emissions. In other words, the opening of a U.K. coal mine is no guarantee that another one somewhere else will not open.

The national government typically does not interfere with decisions of local authorities, but it has the right to do so. In January, Robert Jenrick, the minister who holds that power, declined to exercise it. In light of the CCC’s comments, campaigners are now calling on Jenrick to reconsider the decision and stop the mine opening, though there’s no indication he will change his mind.

These kinds of local and national government clashes over climate and resource extraction are expected to intensify. It’s one reason, for example, that even China’s state-led economy is struggling to decarbonise as quickly as its goals demand. Even there, coal mining and other emissions-intensive industries have a tight grip on local economies and politics.

“The solutions need a bit more imagination and creativity” to hold officials accountable, said Doug Parr, Greenpeace UK’s chief scientist.

One way to ensure a climate-aligned outcome in such conflicts, says Willis at the Lancaster Environment Centre, is for national governments to set out clear dates on when different types of carbon-intensive activities are to be phased out entirely. The UK has a goal to phase out coal in electricity generation by 2025, but no such deadline on the mining of coal, leaving wiggle room for places such as Cumbria.

Akshat Rathi writes the Net Zero newsletter, which examines the world’s race to cut emissions through the lens of business, science, and technology. You can email him with feedback.