Aer Lingus CEO Dermot Mannion has written to SIPTU's president Jack O'Connor expressing his anger about last Saturday's unofficial stoppage which caused serious disruption to passengers throughout the day.
In the letter, he says that as a result of the industrial action, Aer Lingus has launched an official investigation into the organsiation and execution of the unofficial work stoppage.
He warns that the investigation may lead to disciplinary action.
The pay of all staff involved will be deducted for the period of the stoppage.
Mr Mannion accuses the workers of showing complete disregard for customers by giving no prior notice of their stoppage.
He says the dispute marks a serious and very worrying development in Aer LIngus's relationship with SIPTU.
He says the action is all the more disappointing given the unprecedented competitive pressures facing the airline.
He points out that Aer Lingus's main competitor in Dublin - Ryanair - does not recognise unions and as such has a staff cost base that gives them a consequent competitive advantage.
He stresses the need to implement the terms of the Labour Court recommendation on flexibilities and new work practices.
He also points out that the Board of Aer Lingus has approved the purchase of $2.4 billion worth of aircraft in coming years, subject to implementation of the savings invisaged in the restructuring plan.
It emerged this evening that the airline has set a deadline of the 1st August for implementation of its costcutting proposals at the airline.
In letters to senior officials of SIPTU and IMPACT, Chief executive Dermot Mannion said the company was facing unprecedented competitive pressures - and must respond urgently by delivering a lower cost base.
