The company's chief executive, Michael O'Leary, said that Ryanair's Shannon-Paris route will be closed and the Shannon-Gatwick and Shannon-Stansted services will be less frequent.
Speaking at a press conference in Limerick this afternoon, he said the decision to cut services at Shannon comes on the back of the announcement last week by the Dublin Airport Authority to increase airport fees at Shannon by 33%.
He also blamed the Government's €10 tourist tax.
Earlier, the Ryanair boss claimed his airline would seek permission to use only one pilot per flight because he believes co-pilots are unnecessary.
A spokesman for the British Airline Pilots' Association dismissed the suggestion as a publicity stunt.
'His suggestion is unsafe and his passengers would be horrified. Are there no lengths to which he will not go to get publicity?' said Generral Secretary Jim McAuslan.
Mr O'Leary, who has previously claimed to have considered standing tickets on flights as well as charging for the use of toilets, conceded that two pilots would be needed on long-haul flights but said on shorter trips flight attendants could do the job.
In an interview, he said the second pilot was only there to 'make sure the first fella doesn't fall asleep and knock over one of the computer controls'.
FlyersRights.org founder Kate Hanni told the Telegraph: 'He insults the dignity of the flying public every time he opens his mouth.'
