Luas workers have announced two more strike days , on March 8 and 17 ( St Patrick's Day).

The two days are in addition to strikes planned for Thursday and Friday of this week, and to last week's two-day strike with affected more than 90,000 Dublin commuters.

The protests are being organised in a bid to seek a pay rise of up to 54% over the next five years.

Managing director of Luas operator Transdev Gerry Madden said he was "flabbergasted and really shocked" by the timing of the strike on St Patrick's Day in particular.

"This goes beyond affecting Dubliners now. This affects people who have long since made plans to come up from the country and enjoy Paddy's Day and the parade," he said.

"I'm really sorry to (sic) those customers who have already been affected by these strikes and new ones who will now be affected…(This is) no way to try to resolve a dispute."

He previously apologised to users for last week's strikes, saying: "“(We are) very disappointed that Siptu have chosen to take this action, we have been working tirelessly to try and get them to modify their claim and call of these strikes."

Transdev claims each strike day will cost it €100,000.

Eoin Reidy of Siptu has accused Transdev of trying to demonise Luas workers and said: “Instead of attacking its employees, the management of Transdev would be better served considering why over 99% of Luas workers feel so frustrated that they voted for industrial action…

"Siptu members hope that the company will reconsider its position and make a meaningful offer on pay.”

Today he added: "When we have a dispute like this, it's a failure of the process and we all have to take our share of the blame, but I think it would be wrong for the workers to take a disproportionate share of the blame.

"(They) have never, ever gone on strike since the inception of the Luas. 99% of them voted for this action, and they didn’t take it lightly."