A perk which allowed dozens of pilots to fly cheaply into Ireland to work for Aer Lingus has been stopped as a result of the industrial action which is under way.

An indefinite work-to-rule by Irish Air Line Pilots' Association (IALPA) members at the airline began at midnight on Wednesday as part of an ongoing pay dispute.

There is also a planned eight-hour strike on Saturday.

Some pilots choose to base themselves in the UK and commute due to the high cost of living in Ireland, according to IALPA.

Around 100 pilots avail of the company travel scheme regularly, which allows them to book seats cheaply once there is availability on flights, one source told RTÉ.

The holiday plans of pilots based in Ireland - who also avail of discounted flights - are also being disrupted.

Pilots in Aer Lingus, along with other staff, can avail of one discounted ticket for their family - which many use to book holidays.

A letter sent to all pilots by Aer Lingus in relation to the action revealed that pilots who are based in the UK and arrive to work here using discounted flights will lose this privilege while the industrial action is ongoing.

Around 100 Aer Lingus pilots live in the UK and commute to Ireland for work

"The priority of Aer Lingus now is to mitigate the significant disruption that is being caused to our customers by IALPA's proposed industrial action and, where possible, to re-accommodate those customers impacted," wrote Aer Lingus Chief Operating Officer Adrian Dunne.

"As a consequence, and effective from 26 June 2024, all staff travel privileges, and tickets (including those already issued) for those IALPA / Forsa members who participate in this industrial action" will be "suspended until further notice" along with any tickets for "qualified relatives", the letter said.

Bookings made for June and July will be "cancelled and refunded" while "bookings beyond this timeframe will be kept under review", it added.

In response to Mr Dunne, IALPA responded in a letter that said: "You will be aware that Aer Lingus has a significant number of pilots, mainly First Officers, who commute to work from abroad using Aer Lingus staff travel due to the hight cost of living in Dublin.

"This high cost of living has been compounded by the lack of a pay increase since 2019, with pilots enduring a 50% pay reduction for a prolonged period during the pandemic.

"Withdrawing pilots’ methods to commute to work can only increase the level of stress on our pilot body.

"IALPA is requesting that you review the threat of staff travel withdrawal as it is most unhelpful in the current environment."