Aer Lingus members of the Irish Airline Pilots’ Association (Ialpa) have over the past fortnight twice voted convincingly in favour of action up to and including strikes, with the union serving the carrier notice of its intention to take action starting next Wednesday (26 June).

Rather than a full walkout, this action will take the form of a strict work-to-rule policy, which will see Ialpa’s Aer Lingus members refuse to work overtime or beyond their contract hours, and reject management requests to change their rosters.

It comes just days before the summer peak season, during which Aer Lingus is expected to carry up to 40,000 passengers a day. The action will be limited to pilots employed by Aer Lingus directly in Ireland, and won’t extend either to Aer Lingus Regional services between the UK and Ireland operated by Emerald Airlines.

“Please be advised Aer Lingus Regional flights, operated by Emerald Airlines, are unaffected by this industrial action," said Aer Lingus in a statement. "Transatlantic flights to/from Manchester are also unaffected by this industrial action."

However, the carrier warned: "The nature of this industrial action will cause a significant impact on our flight schedules."

It said the action would have a "wholly unnecessary" impact on passengers flying in the coming weeks during "peak holiday season for families". The carrier added it would be communicating directly any impacts of the action to third-party agents. "It is inevitable there will be disruption," it added.

Talks to find a resolution are understood to have stalled, with Ialpa continuing to seek a more than 20% pay increase for its members, who voted overwhelmingly to reject a labour court recommendation of 9.25%.