Staff at Dublin, Cork and Shannon airports are set to vote overwhelmingly in favour of industrial action over the planned withdrawal of their right to discount travel on Aer Lingus flights.

The TEEU, MANDATE and IMPACT have all voted in favour of action and the result of a ballot of SIPTU workers in Cork and Shannon is expected this evening. The Dublin Airport Authority, which manages the  three state airports,  has described the threat of industrial action as a disproportionate response to the issues involved.

Aer Lingus had originally announced that its withdrawal of the travel concession would take effect at the end of last year, but the airline extended the deal until the end of February to allow further discussions.

Aer Lingus says it is withdrawing the concession for airport staff because the cost of administering it is prohibitive. It also says that the aviation market has changed, and that flights can now be purchased for as little as €3.

A spokesperson said a meeting was scheduled for Friday between Aer Lingus and the Dublin Airport Authority to consider the matter.

The unions argue that the travel concession is one of the conditions of their employment, the protection of which is enshrined in last year's State Airports Act which is intended to break up Aer Rianta into three separate airport authorities at Dublin, Cork and Shannon.