Maastricht Journal of European and Comparative Law

Although initially seen as politically and institutionally impracticable, the link between solidarity and the EU budget has since evolved into a fundamental pillar of the EU's current integration momentum. While successive crises have broken the long-standing taboo surrounding the notions of ‘solidarity’ and ‘distribution’, particularly within the realms of EU financial and budgetary governance, academic and judicial efforts are seeking to clarify the legal meaning of solidarity and to identify its normative dynamics within the EU legal order. In parallel, the EU budget has undergone a transformation in size, flexibility and scope of action, progressively embedding the distributive mandate of solidarity, though not without limitations, into its structure and mechanisms. Against this background, this paper examines the interplay between solidarity, budgetary instruments and emergency frameworks. It first sheds light on the rationale and operational dynamics of interstate solidarity, framed as a general principle of EU law, and then explores why the EU budget serves as a key mechanism for operationalizing solidarity, and how this function evolves in response to emergencies.

This article examines the Charter horizontal enabling condition as a novel mechanism for enforcing fundamental rights through EU funding under the 2021–2027 Multiannual Financial Framework (MFF). Notwithstanding its greater relevance in the financial enforcement of Article 2 TEU values, the Charter horizontal enabling condition has received limited scholarly attention so far, especially in comparison to the Conditionality Regulation. The article contributes to this emerging debate by analysing the origins, design and practical application of this instrument in the 2021–2027 financial period, focusing particularly on the cases of Hungary and Poland. It shows how the Charter horizontal enabling condition has provided the Commission with a versatile and procedurally straightforward tool to address fundamental rights breaches by the Member States affecting EU funding management. While acknowledging its significance in enhancing the protection of fundamental rights in the framework of EU funding, the article highlights the main shortcomings that have emerged in practice, notably regarding transparency and legal certainty. The article concludes by providing a preliminary assessment of the Commission's proposal to introduce a ‘Charter horizontal condition’ in the upcoming MFF, along with recommendations for improving the mechanism in future budgetary negotiations.

This article examines the SAFE Regulation, a key component of the ‘White Paper for European Defence: Readiness 2030’, as a central innovation in EU defence financing and fiscal governance. Drawing on the pandemic-era experience of SURE and the Recovery and Resilience Facility, SAFE enables the EU to issue loans to support Member States’ defence investments through coordinated spending. The article advances three main arguments. First, it shows how the instrument operates outside the Common Foreign and Security Policy budgetary regime while nonetheless contributing to the Treaties’ objective of progressively framing a common defence policy. Second, it critically analyses the unprecedented reliance on Article 122 TFEU as the legal basis for defence-related financial assistance tool, highlighting the legal and institutional tensions this choice generates, including the marginalization of the European Parliament and the pending annulment action. Third, the article assesses SAFE's broader implications for EU economic governance, arguing that joint EU borrowing is no longer confined to crisis response or market access emergencies but is increasingly deployed as a proactive policy tool to expand national fiscal space and coordinate strategic investments. Overall, the article contends that SAFE reshapes the EU's understanding of financial solidarity, advancing a model of risk-sharing and preparedness that may inform future integration in other strategic policy areas.

The EU budget now stands at its recurring turning point: the next Multiannual Financial Framework (MFF) for 2028–2034. This article examines a dimension of this budget considerably underexplored – its social legacy – and takes this legacy to interrogate the trajectory of budgetary integration, including the current MFF proposal, and its delicate balances of market, social, spatial and lately geopolitical concerns. The analysis centres on the European Social Fund, which seeks to improve working and living conditions since the 1957 EEC Treaty. I first trace the budget's social legacy to the early Community, before cohesion policy was formally operationalized in 1988. This perspective is a story of reversibility: the budget's development was not linear or inevitable, and past ambitions can contest present institutional projects. The article's second part analyses the social dimension of the Commission MFF proposal. In a turn to competitiveness, security, and budgetary ‘flexibility’, a risk of retreat from budgetary social policy unfolds across three dimensions: structure and availability of funding, articulation of social policy objectives, and how the budget embeds social policy within economic governance. Eroding this social legacy reshapes the political economy of EU budget law, which risks further detaching the Union from the lived experiences of those it governs.

To allow for large-scale common EU borrowing of over €1 trillion for NextGenerationEU, SURE, SAFE and assistance to Ukraine, the EU significantly adapted its legal framework since 2020, consolidating national borrowing capacity with centralized EU debt issuance. This article examines the main features of this new era of common EU borrowing, detailing both the legal and financial architecture underpinning this policy. Financially, EU borrowing aims to achieve better market access and enables tax smoothing, making assistance viable only as long as it improves the fiscal position of the Member States. Legally, the EU has created an elaborate system of guarantees and secondary laws to assure creditors that it is legally obliged, able and financially capable of honouring its debt. The article also discusses the financial implications of borrow-to-spend instruments on the budget, and the legal adjustments in the current and future Multiannual Financial Framework designed to meet financing needs for these borrowing costs.

The article explores the European Union's system of own resources, a foundational yet often underexamined aspect of EU integration. Tracing its evolution from the EEC Treaty to the current framework, the article assesses the conceptual ambiguity surrounding the notion of ‘own resources’, the limits of the EU's financial autonomy and the institutional challenges arising from the unanimity requirement and the limited involvement of the European Parliament under the procedure laid down in Article 311 TFEU. The paper then examines recent initiatives, with particular attention devoted to the proposal for a new own resources decision presented by the European Commission in July 2025, in anticipation of the next Multiannual Financial Framework (2028–2034). Against this background, the contribution investigates the current and prospective relevance of own resources as a financing mechanism for the EU, notably in comparison with ‘other revenue’ under Article 311, second paragraph, TFEU. The discussion concludes with open questions concerning the reform of the decision-making process and the possible development of the EU's fiscal base, with a view to enhancing financial autonomy and policy coherence.