Radical-right political actors have the potential to influence and polarize political discourse, posing challenges to democratic consensus-building on critical issues such as climate change. In the context of an accelerating climate crisis, effective climate action requires both democratic majorities and broad public support – conditions that polarization can undermine. This article investigates the impact of radical-right politicians, often the most climate-skeptical voices, on parliamentary debates on climate change. Employing a novel supervised learning approach, I identify climate-related content in parliamentary speeches and, using established multilingual transformer models, analyze the emotions and moral appeals embedded within these speeches. This approach allows me to provide empirical evidence on the radical right’s potential to shape the political discourse on climate change across multiple national European parliaments and to shed light on the divide between radical right and green parties – representing the strongest advocates in the fight against climate change. Furthermore, I leverage the staggered entry of a radical-right party into German state parliament to make the findings more robust.