Ryanair has confirmed that 20 flights between Ireland and the UK will be cancelled, affecting 3,500 passengers, as a result of industrial action next Friday.
It means that a significant number of passengers are facing travel disruption over the upcoming August bank holiday, after Irish-based pilots announced a fourth day of strikes.
Trade union Forsa representing the pilots, announced pilots would down tools on August 3 as part of their ongoing dispute with the company.
Ryanair confirmed yesterday that 20 flights between Ireland and the UK will be cancelled as a result of the move.
The low-fares airline claimed a "small minority" of Irish-based pilots called for the fourth day of strikes after Forsa "rejected our offer to meet yesterday".
"We regrettably have cancelled just 20 (7pc) of our 300 planned flights to and from Ireland next Friday," it said.
It said passengers affected have been contacted by text message and will be "refunded or readily re-accommodated on other Ryanair flights".
However, Forsa said that pilots believe the company's decision to issue a protective notice to 300 of its staff on Wednesday was "a provocative act" that has only served to "escalate the dispute".
It said that the move "demonstrates management's unwillingness and/or inability to implement the airline's declared intention to agree working conditions with its staff by negotiating with their chosen trade union representatives."
Meanwhile, the European Cockpit Association (ECA) representing pilots across Europe, said Ryanair's announcement of a 20pc cut in its Dublin-based fleet this winter and the possible "dismissal of 100 pilots and 200 cabin crew" in the "aftermath of a series of one-day strikes" is one that will "fuel frustration among its workforce even further".
It also accused the company of 'union busting.'
In response, Ryanair stated that: "Moving aircraft is not union busting.
"As our statement yesterday, made clear all affected pilots and cabin crew will be offered transfers to Poland.
"We respect the right of people to join unions and go on strike, as 25pc of our Irish pilots have done three times in the last three weeks.
"Having signed union recognition agreements in bigger markets like the UK, Italy and Germany, this allegation of union busting is disproven."