Ryanair chief executive Michael O'Leary has written to Aer Lingus chairman Colm Barrington asking him to clarify recent statements made by Aer Lingus management following Ryanair's takeover bid.
In the letter, Mr O'Leary listed a number of issues - including Aer Lingus's elimination of long-haul fuel surcharges - and asked what effect they would have on profits for this year and next year.
He also asked Mr Barrington how much the recently announced restructuring would cost, and about the airline's defined benefit pension scheme.
Mr O'Leary also asked the airline to confirm its profit forecasts for both 2008 and 2009 in the light of the issues he had raised. He said Aer Lingus had forecast an operating loss of around €20m this year and €70m last year.