Ryanair, which launched a business class service last year, would like to operate flights between up to 14 European and US cities.
A Ryanair spokesman said the board had approved business plans for future growth, including transatlantic, and that the company was in talks with manufacturers about long-haul aircraft.
"European consumers want lower cost travel to the USA and the same for Americans coming to Europe," he said. "We see it as a logical development in the European market."
The spokesman added that the business plan was dependent on securing "viable" long-haul aircraft and that the company estimated that to be "four to five years away".
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