Ryanair boss Michael O'Leary has faced calls to quit as the fiasco surrounding the airline's decision to cancel thousand of flights continues to grow.

Earlier this week, the Irish airline announced it would cancel 18,000 flights between November and March across 34 routes. The move will affect approximately 400,000 passengers and came two weeks after a shortage of pilots forced the carrier to cancel between 40 to 50 flights a day until 31 October, affecting approximately 315,000 passengers across 2,000 flights.

Speaking on Thursday (28 September), Labour MP Graham Stringer, who sits on the Commons transport committee, said O'Leary should take responsibility for his actions.

"He has let passengers down," he was quoted as saying by the Evening Standard.

"He has let his shareholders down. Nobody can continue with that level of failure."

His stance was echoed by Ed Davey, a former cabinet minister for the Liberal Democrat, who called for radical changes to be made within the Irish airline's hierarchy.

"Given the misery inflicted on tens of thousands of passengers, heads need to roll at the very top of Ryanair," he added.

O'Leary also came under fire from former Conservative transport minister Stephen Hammond, who said Ryanair needed to "understand the concept of corporate honesty" and show the public contrition.

"If they do not, Mr O'Leary must be made to consider his position," he added.

The scathing attack come a day after the Civil Aviation Authority (CAA) warned the carrier it faced legal action for "persistently misleading passengers" about their rights over cancelled flights.

On Wednesday (27 September), in a letter addressed to the Irish carrier, the CAA warned Ryanair it faced "enforcement action" for failing to give customers accurate information after announcing almost 700,000 passengers would be affected by flight cancellations over the next six months.

"There are clear laws in place, which are intended to assist passengers in the event of a cancellation," said CAA chief executive Andrew Haines.

"We have made this crystal clear to Ryanair, who are well aware of their legal obligations."

O'Leary has vowed to fully cooperate with the CAA but Haines warned his promises had to be taken with "a pinch of salt" as he urged the airline to get its act together, adding he was "furious" at the "disregard for consumers and for the law" displayed by Ryanair.

"They told us that last week and yesterday they continued to put out information that wasn't accurate and was misleading to people so I take that statement with a pinch of salt," Haines told Sky News.

"Let's see action not words."

Meanwhile, the airline has also published a list of all the cancelled flights from London Stansted airport between 1 November and 24 March, as well as of the flights that have been cancelled from other UK airports over the same period and of the 34 routes to be affected by the winter schedule change.