As the host of a high-stakes climate summit, Britain has made clear that international agreement on the phasing out of coal, the planet’s most polluting fossil fuel, is a top priority.

The British president of the COP26 summit in Glasgow, Alok Sharma, talks about the need to “consign coal to history.”

And Britain is among countries pledging this week to end all investment in new power generation from coal, internationally and domestically.

At the same time, however, Britain is mulling whether to approve what would be its first new deep coal mine in more than 30 years.

This week’s pledges would not apply to the mine being contemplated, because the coal taken from it would be used in iron and steelmaking rather than being burned to generate electricity.

Nonetheless, critics say a new mine would increase global emissions and be a bad look at a time when the world is watching. The mine proposal has attracted unfavorable attention from the likes of the teenage climate activist Greta Thunberg and U.S. climate envoy John F. Kerry.

Supporters, including many in this Georgian town in northwest England, say it would bring prosperity to an area that is postcard-pretty but struggles economically. They also argue: If Britain is going to burn coking coal to make steel, for many years to come, why not burn local, English coal that doesn’t need to be imported and can be produced at mines they can monitor?

The proposed mine has become something of a political headache for Prime Minister Boris Johnson, who is trying to lead on climate but who also campaigned on a pledge to promote economic activity in the north of England. In a BBC interview at COP26, Johnson said, “I’m not in favor of more coal,” but he also said the decision wasn’t up to him.