Ryanair (RYA.I) launched its third offer in five years for Irish rival Aer Lingus in June, a 694-million-euro bid that the former state carrier has urged shareholders to reject, while it is also interested in buying a slice of London's third-biggest airport.

Europe's competition regulator last week launched an in-depth review of Ryanair's latest Aer Lingus (AERL.I) bid, signalling the airline may have to make big concessions to ease competition concerns or face fresh failure.

"We are confident that the remedies package will be enough to satisfy competition issues," Ryanair's chief executive Michael O'Leary told a news conference in London.

"There are 46 cross over routes and we will remedy all of them by getting airlines to come to Dublin and take them over," O'Leary added, referring to routes on which both Ryanair and Aer Lingus operate.

A source familiar with the matter has told Reuters the company was talking to British Airways (ICAG.L) and Virgin Atlantic about possibly opening routes and divesting airport slots.

Ryanair, which already owns 30 percent of Aer Lingus, had an initial bid turned down by the European Commission in 2007 and dropped a second offer in 2009.

O'Leary also said Ryanair was seeking no more than a 24.9 percent stake in Stansted airport and was in talks with "a number of potential bidders" who want the airline involved in a consortium bid for the airport.

British airports operator BAA opened the way for a $2 billion sale of London's Stansted at the end of August, with Manchester Airports Group MAG.L an early frontrunner in a bid battle expected to draw U.S. banks, pension funds and Asian operators.

"We want a stake of nothing more than 24.9 percent in Stansted. It would cause regulatory problems if we were seen to have too large a share in an airport," O'Leary said. (Reporting by Rhys Jones; Writing by Lorraine Turner in Dublin; Editing by Mark Potter)

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