American Airlines has confirmed that it is ending its transatlantic service out of Shannon in October.
The company currently operates a daily service from Shannon to Chicago. American Airlines has been operating from Shannon since 2005, when it began a daily service to Boston.
A spokesman for the company confirmed that its service out of Shannon will discontinue from 1 October and it will be focusing on its Dublin-Chicago service.
He said that the airline had examined the overall economics of its services from Ireland in the light of the Open Skies policy.
The move has been described as very sad news for Shannon and there are fears that it is the start of a withdrawal of transatlantic services from the airport.
Fine Gael's Pat Breen said it was the start of the negative effects of Open Skies.
Independent James Breen accused the Minister for Transport, Martin Cullen, of failing to carry out a much needed impact study on the effect of Open Skies. He added that he is now fearful that Shannon will have no transatlantic services.
Fianna Fáil’s Tony Killeen said he does not believe the news will come as any great surprise, since Open Skies will mean that some operators will move to consolidate their operations in Dublin, while others like Delta and Continental will move to develop their services from Shannon.