Abstract: Regime complexes entail a variety of institutions with a degree of overlap in terms of thematic issues and participating actors. The EU is such an actor engaging with other governmental and non-governmental entities in the formation and evolution of regime complexes. In this article, we examine the role of the EU in the international transport regime complex, and more specifically in two of its core international organizations, namely ICAO and IMO. Our actor-based approach focuses on how the EU navigates between these two constitutive components of the global transport regime complex, advancing climate change mitigation measures. Our empirical material shows how the EU’s active engagement in ICAO contributed to the organization’s shift vis-à-vis the role of the aviation industry in greenhouse gas emissions. Besides the EU learning process that occurred and led to a more engaging and less conflictual EU approach in IMO, the ICAO achievement increased pressure and created a more conducive environment for the respective recognition of the maritime industry’s share in climate deterioration. In this respect, the EU benefited from the structure of the transport regime complex to pursue its own preferences.
Keywords: climate diplomacy; European Union; ICAO; IMO; transport regime complex