Luas staff are to stage further strike action over Easter.
The Dublin trams will not run on Easter Sunday or Bank Holiday Monday.
The Luas operator Transdev says it is "extremely disappointed" with SIPTU and Luas drivers - and believes its shows "a total disrespect" to all those who wish to mark the 1916 commemorations.
In addition to stopping the service on Easter weekend, SIPTU also plans to stop the service next Tuesday March 8th and St Patrick's Day - March 17th.
Gerry Madden, managing director of Transdev, said: "SIPTU are not just threatening the company with their unrealistic pay claims but are now prepared to jeopardise the Irish economy and Irish jobs".
"The State has made great plans for the centenary of 1916 and transport is a vital part of those plans", he added.
Transdev has stated it is willing to attend the Workplace Relations Commission (WRC) and was disappointed the invitation had to be withdrawn because of last weeks' "unofficial action by some Luas drivers", Transdev says.
"Now that the unofficial action (the taking of personal needs breaks) has stopped, it is deeply regrettable that this notice was served", it adds.
