Britain's first new deep coal mine in decades was approved unlawfully, as ministers neglected to assess the negative global implications of this contentious decision, environmental activists informed London's High Court on Tuesday.

Friends of the Earth and South Lakeland Action on Climate Change are contesting the 2022 approval of the coking coal mine in northwest England by the former Conservative government. Legal documents presented by SLACC's attorneys argue that the ministers overlooked the potential damage to Britain's reputation as a climate frontrunner and the possible encouragement of other nations to authorize new fossil fuel projects.

Following a Supreme Court decision that planning bodies must evaluate the consequences of both extraction and combustion of fossil fuels, Britain withdrew its defense against these legal challenges. However, the developer, West Cumbria Mining, continues to defend the project, claiming it to be a 'net zero' mine, intended for steel production rather than electricity generation. West Cumbria Mining's attorney, James Strachan, maintains that the mine would not contribute to net greenhouse gas emissions, as its coking coal output is driven by steel demand.

Strachan further asserts that the mine's approval would enhance Britain's global standing by fulfilling domestic coking coal needs. Conversely, the campaign groups' lawyers emphasize that the international repercussions of the mine's approval were crucial to the planning debate and were disregarded by the ministers. Friends of the Earth's attorney, Paul Brown, highlights that the issue is not about the UK's climate advocacy, but about the potential reduction in Britain's influence on international climate negotiations.

The court hearing is scheduled to conclude on Thursday, with a verdict expected in the future.