The European Union as an international climate actor

The European Union’s (EU) emergence as a global climate actor illustrates the specificity of its legal and institutional construction, which balances limited conferred competences with ambitious external objectives. While lacking traditional state sovereignty, the EU leverages its competences and principles to participate in and implement international climate agreements such as the the Paris Agreement. Its credibility as a climate actor is reinforced by internal measures like the European Climate Law and the Carbon Border Adjustment Mechanism, alongside the strategic use of its exclusive common commercial policy to promote climate objectives in trade agreements. The Union’s withdrawal from the Energy Charter Treaty illustrates both the legal constraints and opportunities of its external climate action: despite its inability to compel member states to withdraw, the EU used its exclusive competences and the principle of loyal cooperation to align national actions with its climate goals. Through instruments such as the Global Gateway and the Samoa Agreement, the EU integrates climate diplomacy with development and investment strategies. This progressive integration of climate objectives into external action positions the EU as an emerging normative green power in global climate governance, despite ongoing geopolitical and structural challenges.