Aer Lingus cancelled return flights to Heathrow from Dublin and Shannon on Thursday, the airline confirmed.
The carrier dropped one return service, that is two flights, from and to Shannon Airport, to comply with a 100,000-a-day passenger limit imposed last week by Heathrow until mid-September.
A technical issue forced Aer Lingus to cancel a return flight from and to Dublin, also on Thursday.
The airline said it deeply regretted the impact of cancelled flights on customers, but noted that due to the frequency of services between the Republic and Heathrow, it could re-accommodate most customers on other flights on the same day.
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Aer Lingus added that it would contact all customers to inform them of their rights, including re-booking or refunds.
Heathrow last week told airlines that it would limit passenger numbers to 100,000 a day until September 12th as problems such as delays, missed flights and lost baggage mounted past that point.
The move has hit services between the Republic and the London hub, used by many Irish people travelling to Britain or transferring to destinations not served from airports here. Aer Lingus is one of the biggest holders of slots at Heathrow.
Heathrow chief executive John Holland-Kaye noted that airlines’ total capacity at the airport up to the end of the summer totalled 104,000 passengers a day, 4,000 more than it could handle.
