The study of European integration has traditionally focused "inside-in" on the internal development of common laws and policies. With the maturing of the single market and the evolution of EU external relations, attention has shifted beyond the EU to the ways in which the EU intentionally and unintentionally projects its norms beyond its borders - the "inside-out" dynamics of European integration. This panel explores a step further in the research on EU integration: the reverse influence of third countries on EU laws and policies.

The inside-out movement was reflected in the processes of EU enlargements; the intensification of association relations with western, southern and eastern neighbouring countries which, either willingly or unwillingly, did not join the EU; and the development of EU actorness in trade, foreign and security relations. Three decades later, association relations with the EEA/EFTA countries, Switzerland, the countries of the European Neighbourhood Policy (ENP), and other privileged trade partners have tightened mutual political, administrative, and legal links between the EU and the countries in its neighbourhood. The participation of third countries in the EU’s structures, programmes and policies, and their adoption of EU norms is increasingly studied alongside the EU's internal differentiation under the notion of external differentiated integration. The UK's withdrawal from EU membership has moved the country into this category of deeply interdependent third countries, giving new urgency to the search for sustainable arrangements that foster association while preserving the autonomy of both parties. An increasingly challenging geopolitical context including Russia's war against Ukraine, new East-West antagonisms as well as mounting transnational challenges such as the fight against climate change, migration policy, and energy supply have added to the importance of finding flexible solutions to sustain partnerships with associated countries.

This conjuncture of consolidating ties and sharing external challenges warrants the opening up of EU-studies towards greater attention to factors that influence the process of European integration beyond the EU and its member states.The panel explores third country influence from the perspective of differentiated integration. It discusses the levels at and venues through which third countries can exert influence, and the legal and the legal constraints and political implications of these processes.

Given its depth and ambition, the Association Agreement (AA) concluded between the EU and Ukraine may have been expected to result in significant reverse influence on the EU. However, this paper shows that this influence is indirect, arising from mechanisms and international processes brought into sharp relief by the AA. These are: the power asymmetry between the parties, politicization of the agreement and geo-politicization as a form of contestation of the agreement in the geopolitical arena, stirred by Russia's grievances. The paper argues that in responding to the asymmetry, politicization and geo-politicization of the AA, the EU has been pushed to innovate to prevent the legal and political failure of the negotiated agreement. Innovation occurred at different levels: at institutional level to assist Ukraine's capacity to implement it, at constitutional level to ensure its ratification given politicization in the Netherlands, and at policy level to address Russia's geopolitical moves.

This paper explores differentiated integration based on a decentred conceptualization of European Union (EU) international influence, by focusing on the external ramifications of its internal policies. We treat the EU's international role less as that of an emerging unitary actor than as a conglomerate of loosely coupled sectoral regimes – the EU’s administrative space - whose prescriptive scope extends to third countries. The EU's administrative space is composed of sector-specific European agencies embedded in various forms in networks of competent national authorities in nearly every area of EU policy. Such networks often include third-country authorities. This constitutes a trans-governmental layer of integration among national public authorities both from EU member states and – to a certain extent – third countries. We thus ask how do scientific and regulatory networks contribute to fueling the EU’s administrative space’s centrifugal dynamics? We compare three sectors public health, energy and migration. While cases are most different regarding the nature and strength of the network structuring each sector, they all present a particular sensitivity to crises. The context of crisis is not only relevant because of the EU’s state of permacrisis, it also shows the extent to which networks are able to rapidly mobilize their members, deal with ambiguity and learn from crises. Our findings show that networks are instrumental in fostering third country participation, but with importance differences between sectors in times of crisis. This is due to differences in network structure, European agency role and network composition (scientific, regulatory or stakeholder organizations).

The expansion of the European Union's (EU) regulatory sphere creates conflicts of sovereignty between the EU and its member states, and third countries that lack a possibility to participate in the making of those laws and policies. The conflict is epitomised in the concept of the Union's decision-making autonomy. Albeit stringently applied, the concept is ambiguous and undefined. This article endeavours to unfold its meaning, use and significance and examine whether its rigid nature is justified in light of the Union's aims to expand its regulatory sphere. The article argues that the ultimate rationale of decision-making autonomy is to ensure the effectiveness of the EU legal order and to compensate for the member states' loss of sovereignty, investment and risk-taking. Insofar as non-member states do not demonstrate similar commitment to the EU, exclusion from decision-making is justified to retain the privilege and attractiveness of membership.