Ryanair has reported a 24% drop in net profits for the first quarter of the year.
The Irish budget carrier blamed the losses on the chaos caused by the volcanic ash crisis in the spring.
The airline said the airspace lockdown over Europe caused it to cancel almost 10,000 flights at a cost of 50 million euros.
In spite of the financial dent, Michael O'Leary's airline claimed it was still on course to hit profit targets set out at the beginning of the year.
Speaking to the BBC, Ryanair's chief financial officer, Howard Miller, blamed the authorities for the length of the ash crisis.
"In Ryanair we had one and a half million passengers who were disrupted because of non-existent volcanic ash clouds.
"It was a regulatory disaster, and both passengers and airlines suffered," he said.