Ryanair has called on the DAA to "stop lying to the public about its rip-off car park price hikes".
The DAA today increased its parking charges by 50%, the second 50% price hike since 2005.
This has seen the cost of parking at the DAA monopoly double from €20 to €40 in just two years, according to the airline.
Peter Sherrard, Ryanair’s Head of Communications said: "The only way to address this blatant price gouging is to allow competing terminals at Dublin Airport, which would force the DAA to improve its services and lower costs to the travelling public.
"The only reason why the DAA is able to abuse the travelling public by doubling car park charges is because the DAA is a monopoly with no effective regulator.
"The DAA is today trying to mislead the public about the doubling of car park charges in just the same way as it is attempting to mislead the public about the cost of T2 which has already quadrupled since it was first announced and will lead to a doubling of passenger charges at this out-of-control monopoly.
"Only competition will reduce costs and put an end to this unjustified price gouging of passengers at the DAA monopoly."