The European Union's top court told Poland last month to halt operations at the open-pit lignite mine after Prague complained of environmental damage in nearby Czech villages.
A group of about 2,000 Polish miners has traveled to Luxembourg to protest against the decision of the European Court of Justice to halt production at their lignite mine.
The agency has become the subject of increasing controversy in the past decade over its influence on efforts to stabilize the climate and shift away from fossil fuels.