19As a preliminary point, it should be noted that the EU legislature has laid down the obligations of air carriers in the event of cancellation or long delay of flights (that is, a delay equal to or in excess of three hours) in Article 5(1) of Regulation No 261/2004 (judgments of 23 October 2012, Nelson and Others, C‑581/10 and C‑629/10, EU:C:2012:657, paragraph 40).