Ongoing issues with the Boeing 737 Max has led Norwegian to suspend some Ireland-US services until the end of the year.
Flights from Cork and Shannon will operate from Dublin for the remainder of the summer due to the grounding of the Max.
A Norwegian spokesperson said: "Due to the continued grounding of the Boeing 737 Max by the European aviation authorities, our flights to and from Cork and Shannon will be re-routed via Dublin for the remainder of the summer season.
“Cork is a seasonal route and the reduced availability of aircraft has led to the removal of Shannon services this winter.”
Norwegian passengers due to fly from Cork and Shannon are being told to travel by bus or rail to Dublin and to claim expenses with proof of receipt. The alternative is a full refund.
The airline said: “Customers travelling to and from Cork and Shannon are being re-accommodated onto different aircraft types between Dublin, New York and (Boston) Providence to ensure travel plans can continue with minimal disruption.”
The grounding of the Max is having a serious impact on Shannon, which will lose more than 120,000 seats this year.
Meanwhile, British Airways will suspend its daily BA2272/3 Gatwick-JFK service from 14 January to 10 February 2020.
A BA spokesperson said: "We have temporarily suspended these services to match customer demand.
“We apologise for the inconvenience and are contacting the small number of customers already booked to travel on these services who will be offered refund and rebooking options.”