The LE Samuel Beckett will enter into service in Irish waters early next year, with the LE James Joyce following it in 2015.
The two oldest ships in the fleet, LE Emer and LE Aoife, will be decommissioned and sold by the Irish Naval Service.
Fine Gael TD for Wicklow Andrew Doyle spoke of the two new vessels.
"The recent decision to name the two new vessels after Irish literary figureheads is a welcome one," he said.
"The naming of the two new vessels after world-renowned Irish figures will set the tone both for Ireland and overseas as a nation with a modern Naval Service and one with a strong international maritime presence.
"The Minister for Defence, Alan Shatter TD, has been working closely with the Irish Defence Forces, particularly the Irish Naval Service, to ensure that an adequate number of vessels are patrolling Irish waters at any given time.
"In 2012 alone, some 1,258 patrol days were covered along with 1,329 vessel boardings, ensuring Ireland remains equipped for maritime patrol and maintains a steady fleet of eight patrol vessels," he explained.
The LE Emer will be decommissioned in September and the LE Aoife will follow at the same time next year.