Last month, President Michael D Higgins declined an invitation to the event, saying it was too political.
Sinn Fein says the Government has made the wrong call in its decision to attend a service commemorating the centenary of Northern Ireland.
The Minister for Foreign Affairs and the Government Chief Whip will attend the church service in Armagh.
Britain's Queen Elizabeth's also due to attend the event taking place on the 21st of October.
Last month, President Michael D Higgins declined an invitation to the event, saying it was too political.
However, the Government says its role in this matter is distinct from the Presidents.
Sinn Fein TD Matt Carthy says, President Higgins made the right decision not to attend:
Sinn Fein says the President read the public mood correctly when he decided not to attend a Northern Ireland centenary event.
Michael D Higgins declined an invitation to the church service in Armagh, saying it was too political.
Yesterday government confirmed the Minister for Foreign Affairs and Government Chief Whip will attend the event later this month.
Sinn Fein TD Matt Carthy says they should have followed the President's example
:

Offaly Fire That Claimed Lives Of Boy (4) And Woman (60s) Upgraded To Murder Investigation
New Figures Reveal How Parts Of Kildare Rank Among Worst In State For GP Coverage
Tomorrow Marks 25 Years Since Naas Man Trevor Deely Went Missing As Gardai Issue Appeal
Woman And Young Boy Die In Offaly House Fire
Rent Hike Fears For Students As Lawless’s Department Weighs Change Sought By Private Operators
Taxi Driver Protest Suspended Pending Outcome Of Talks
BREAKING: Green Light For €1.3bn Drainage Scheme Serving Kildare After Court Agreement
Irish Troops Come Under "Small-Arms Fire" In Lebanon