A legal battle over the huge sums in state aid to businesses battered by the COVID-19 pandemic is playing out in European courts, led by Ryanair, the Irish airline that is now one of Europe’s biggest air carriers.

In a litigation plan that could take years to resolve, Ryanair has filed 16 lawsuits against the European Commission challenging application of European Union rules on state aid. The commission’s competition directorate has approved the disbursement of more than €37 billion to national flag-carriers since the beginning of the crisis, according to EU figures.