Ryanair has said it is ending its distribution partnership with Amadeus from December 15.
The low-cost airline says in a statement that the pair failed to reach a new agreement.
Ryanair began discussing GDS distribution at the beginning of 2014, signing first a deal with Travelport and then with Amadeus in September.
The move to third party distribution marked a big departure in the carrier's strategy at the time as Ryanair had consistently pushed its web-only message.
The statement says it will continue to distribution through Sabre and Travelport.
It adds that the Ireland-based carrier will continue to work with Navitaire, which is owned by Amadeus.
A statement from Amadeus simply says it looks forward to continuing "our partnership through Navitaire."