Irish low-budget airline Ryanair has been fined 370,000 euros ($A356,000) by the Netherlands Consumer Authority for hidden costs associated with tickets purchased online by Dutch travellers.
The watchdog said that European regulations had been violated because full costs were unclear, consumers were not given the option to correct mistakes before finalising a booking and the company was difficult to contact and provided information in English, not Dutch.
"Ryanair offered air fares on its website that did not include all foreseeable and unavoidable costs, such as fees and surcharges," it said. "Consumers thus paid considerably more than the air fares that were initially displayed."
Ryanair, which the authority said has since revised the booking process and now provides accurate prices in advertisements, said it will appeal against the ruling.
"The decision of the Dutch consumer authority is littered with errors. Ryanair will appeal this unfounded decision and confirms that its website fully complies with all EU and Dutch consumer protection regulations," a Ryanair spokesman said in a statement.
On Tuesday Ryanair announced an order for 175 Boeing 737-800 planes in a major fleet expansion three weeks after the EU blocked its takeover of rival Aer Lingus.
The massive order was put at $US15.6 billion at Boeing catalog prices, one of the US aerospace giant's largest orders ever, though discounts could bring the total value to much less than that.
The deal "will allow Ryanair to grow its airline to more than 400 airplanes, serving more than 100 million passengers per year across Europe by the end of the delivery stream in 2018," the Irish company said in a statement.
"It will sustain thousands of skilled manufacturing jobs in Boeing and its supplier companies and will represent the largest=ever capital investment by an Irish company in US manufacturing and US jobs," it said.
"This is big deal for Ryanair and for us," said Boeing Commercial Airplanes president Ray Conner in a New York press conference.
"Ray Conner took me out for Saint Patrick's Day and got me drunk, and at the end of the day I signed the contract," quipped Ryanair chief executive Michael O'Leary.
O'Leary said the planes were to be delivered between 2014 and 2018, at a cost similar to that of Ryanair's 2005 Boeing order. Ryanair has an all-Boeing 737 fleet.
He said the company hopes to see growth in Germany, where Air Berlin is cutting back.
"I hope by the end of this year we will be announcing an order for the 737 MAX as well," he added.
US President Barack Obama, who was hosting a visit by Irish Prime Minister Enda Kenny on Tuesday, cheered the deal.
"It's an example of how the progress that's made in Ireland benefits jobs and businesses here in the United States."
The deal was announced after the European Commission on February 27 barred Ryanair's third attempt for approval to buy its Irish rival Aer Lingus.
The EC said passengers would lose out with less competition and higher prices.
O'Leary suggested Tuesday that the company was being penalized for not being a European flag carrier.
"We are still the only European airline merger that has been prohibited in 40 years," he said.
"Europe likes to put non-efficient flag carriers together to make them even less efficient."
The news came one day European aviation giant Airbus - Boeing's fierce rival - announced a record order worth 18.4 billion euros from Indonesia's Lion Air for 234 medium-range A320 jets.