Ryanair is to further reduce its operations at Dublin Airport and transfer 100 jobs to other European countries.
The airline is to cut the number of aircraft based in Dublin during the winter from 14 to 12 and reduce its weekly flights by 150 to less than 850.
Six routes will also be cut, with capacity on 17 others reduced.
Ryanair Chief Executive Michael O'Leary estimates that as many as 400 other jobs could be lost at Dublin Airport as a result of the measures announced today.
"Every million passengers generates 1,000 jobs," Mr O'Leary said.
"Our cuts today will result in another 500,000 less passengers at Dublin Airport, so it's about 500 less jobs in total."
The airline also criticised the under-construction Terminal 2 at the airport, saying the facility should be "transferred to NAMA"
Ryanair in a statement said that opening the facility at a time when passenger numbers at the airport are at around 17 million does not make sense in light of the fact the existing Terminal 1 can cater for 30 million passengers.
"The DAA now proposes to open this €1.2bn white elephant in November, so that it can claim up to 40% price increases which the Dept of Transport ordered the Aviation Regulator to approve in order to protect the viability of the DAA," the statement said.
"This means that Ryanair, Cityjet and Aer Arann passengers using the existing Terminal 1 will now be paying up to 40% higher airport charges to subsidise those few passengers using the white elephant T2.
"The DAA now expects Ryanair passengers to pay for Terminal 2, despite the fact that they’ll never use it."
The airline also called on the Govt to scrap its €10 tourist tax and "follow the example of other EU countries, who have scrapped tourist taxes and returned to tourism growth".
In a statement the DAA said that Ryanair's move was "not related to passenger charges at Dublin Airport, which is one of Europe’s most competitively priced large airports".
"Ryanair’s own business model and the wider economic position has contributed to the airline’s decision to withdraw these services," the DAA said.
Claiming the budget's airline's position "does not stand up to scrutiny" the DAA said: "If, as it claims, charges at Dublin Airport are one of the key reasons that it is reducing capacity this winter, why did those same charges not have any impact on the company’s desire to launch a new range of flights to sun destinations from Dublin this summer?
"Ryanair’s decisions are based on the market, not Dublin Airport’s highly competitive charges."
The body also rejected Ryanair's contentions in relation to T2.
"T2 is a key element of strategic national infrastructure that will be used by passengers for the next half century," the DAA said.
It accused the airline of lying about the cost of the facility, saying the entire cost is just over €600m - around half of the €1.2bn figure mentioned by Ryanair.
" T2 is the right terminal, at the right cost and will help position Ireland to take full advantage of the economic upturn when it comes," the DAA said.