The action arrives just three months just after the airline recommenced flights from Belfast City just after an absence of 11 several years.
Ryanair operates routes to Malaga, Alicante, Krakow, Warsaw, Gdansk and Milan from Belfast International.
A spokesman for the airport reported: “It is disappointing that Ryanair has now determined to withdraw operations from the whole Northern Eire marketplace at the finish of October, acquiring variously experienced a presence in all three nearby airports in recent several years.
“It has been a difficult period for aviation and a time when buyers have to have some balance and faith in the Northern Eire air transportation community.”
Previously on Tuesday, chief executive Michael O’Leary reported the airline was set to strike its target of carrying involving 90m and 100m passengers for the yr to March 2021. It flew 149m passengers in the yr to March 2019.
Shares rose jumped two.1pc to