Ash from the Icelandic volcano grounded tens of thousands of flights
Italy has fined Irish low-cost airline Ryanair 3m euros (£2.5m) for failing to help passengers after cancelling their flights during the volcanic ash crisis.
Italy's civil aviation authority said it knew of 178 cases of passengers who did not receive mandatory assistance, such as food, between 17 and 22 April.
Ash from Iceland's Eyjafjallajokull volcano triggered a massive shutdown of European airspace last month.
A spokeswoman for Ryanair said the allegation was "complete rubbish".
"Ryanair fully complies with EU [Regulation] 261 and has been complimented by the EU," she said.
The ash cloud paralysed many airports and left an estimated eight million tourists and business travellers stranded.
Italy's air agency, Enac, accused Ryanair of failing to provide passengers at Rome's Ciampino airport with drinks, foods and accommodation as required by European law.
Enac found that most other airlines had managed to meet their obligations despite the difficult circumstances.
Ryanair initially insisted it would only refund the cost of passengers' tickets, but later agreed to fully implement European regulations and pay all "reasonable expenses".
Under EU Regulation 261, if a flight is cancelled, those flying with European carriers into or out of the EU have the right to a refund or to be re-routed.
If passengers chose the latter, they have the right to care - such as accommodation and meals - while they wait.