The passenger, who was travelling from Madrid to Brussels, was made to pay a €20 (£17) fine to bring her 10kg luggage onboard, with a judge in Spain’s commerical court later ruling the case could “easily have fitted in the cabin”, BBC News reports.

Ryanair allows only small bags as hand luggage if they can be stowed beneath the seat in front and charges customers an additional fee for carrying anything more than one personal item onboard.

Larger bags can also require a luggage fee.

In its ruling, the court said the woman should be refunded with interest, deeming the policy to be null and void and told Ryanair “to remove it” from its terms and conditions, pointing to a Spanish regulation that allows passengers to take hand luggage onboard at no additional cost.

The judge characterised the charge as abusive, adding that it “curtailed the rights that the passenger has recognised by law”, and declared it invalid in Spain.

However, the passenger’s chance of compensation was dismissed as the judge did not deem the case to have caused enough stress to the claimant.

Ryanair said it would not change its policy.

The carrier said in a statement: “This ruling will not affect Ryanair’s baggage policy, either in the past or in the future, as it is an isolated case that misinterpreted our commercial freedom to determine the size of our cabin baggage.”

The ruling cannot be appealed.