The (slow) redress of the ‘solidarity deficit’ in the EU and the emerging principle of solidarity in EU law <sup/>

This paper argues that a shift in the EU's solidarity arrangement is emerging. Although solidarity is a fundamental value of the EU project, as stated in Article 2 TEU, and in the preamble of the EU Charter where it is placed alongside human dignity, freedom and equality as the four universal values on which the Union is founded, and although the Court has held that it ‘underpins the entire legal system of the European Union’ constituting ‘its very root’, it is underdeveloped in concrete legal and political terms. This has manifested in a range of crises that the Union has become enmeshed in, and its suboptimal responses thereto. This paper flags four recent developments of change: the European Pillar of Social Rights, the NextGenEU recovery fund, the EU's response to the war in Ukraine and the CJEU's recent case law on solidarity. Indeed, there is a growing scholarship that considers that despite solidarity's somewhat ethereal nature, it is not only a theoretically important tool to understand European Union but that it is an EU legal concept gaining in importance – a general principle in the making. This paper identifies the EU Charter's preamble as the anchor for the interpretation of solidarity as a general principle of EU law.