Embattled Ryanair has been told to correct its compensation policy for passengers by 5pm on Friday, with the regulator saying the airline must stop misleading customers over the ability to re-route to another airline.
Ryanair's share price dipped this morning as its flight cancellation headache worsened with the news that the aviation regulator was "furious" with the airline.
Shares were down more than 2.5 per cent in mid-morning trading.
The Civil Aviation Authority (CAA) announced late yesterday that it was launching enforcement action against Ryanair for "persistently misleading passengers" with inaccurate information regarding their rights, in relation to its recent spate of cancellations due to mismanagement of pilot holiday.
Ryanair cancellations: The airline has just suspended 34 routes until next year: Here's the full list
And today CAA chief executive Andrew Haines told BBC Radio 4's Today programme that he was "furious" with the airline.
"We are furious that they are not complying with the law and they are not giving customers what they are entitled to," he said. "Continuously they are causing confusion with their customers and that's what I think is unacceptable."
Yesterday, Ryanair announced it had suspended 34 routes up to March next year which involves up to 18,000 flights and 400,000 passengers being affected, in an effort to bring an end to the uncertainty over future cancellations.
It had already announced around 50 flights a day would be cancelled for a six-week period across September and October over the pilot trouble.
Neil Wilson, senior analyst at ETX Capital, said the airline's problem "seems to be spiralling out of control", after yesterday's update. He added that it "does seem there is a shortage of pilots that it's not admitting to".
And Haines said there were clear laws in place to assist passengers, helping minimise both frustration and inconvenience caused.
"We have made this crystal clear to Ryanair, who are well aware of their legal obligations, which includes how and when they should reroute passengers, along with the level of information it provides its passengers," he said, adding that the latest information from the airline "again fails to make this clear".
In a statement today, Ryanair said in response to the CAA action: “We will be meeting with the CAA and will comply fully with whatever requirements they ask us to.”