Introduction. The UK and Europe: conceptualising the UK relations with its neighbours after Brexit

The UK’s departure from the EU has led to a recasting of the UK's relations with its European neighbours. Inspired by the work of John Erik Fossum and his collaborators, which highlights how the UK-Norway bilateral relationship are constrained on the one hand by Norway’s treaty obligations to the EU as an EEA signatory and on the other by the two Agreements (Withdrawal Agreement and Trade and Cooperation) signed by the EU with the UK, this project applies a conceptualisation of bilateral relations between the UK and European states as one side of a triangle that interacts with the other two to the EU, the UK and 14 European states (12 member states plus Norway and Switzerland). This paper introduces the project and sets out its overall aim and purposes. It introduces the triangle metaphor, showing how it takes into account political factors and power dependencies, as well as the formal legal rules and informal norms that structure each of the three relationships, accommodates cross-national and cross-sectoral variation along each one of its sides, and how it can be used to capture how relationships are affected when there is a change in the external environment and whether the impact is symmetrical or asymmetrical in regard to the three relationships. Obvious instances include the effects of Russia’s full-scale war in Ukraine, the uncertainty in security and in trade related to the Trump administration, and the geoeconomic challenge posed by China. It