Minister for Foreign Affairs Eamon Gilmore has said those responsible for the deaths of 60,000 people in the Syrian conflict have to know there will be consequences for their actions and they will be brought to justice.
Ireland and three other EU countries, Austria, Slovenia and Denmark, have written a joint letter to the UN Security Council calling for Syria to be referred to the International Criminal Court.
Mr Gilmore also said it is deplorable that Syrian President Bashar al-Assad has not heeded repeated calls for a peaceful transition of power.
Speaking on RTÉ's Morning Ireland, the Tánaiste said the international community could not stand by and do nothing.
He said: "Those who are responsible for the slaughter, those who are carrying it out and those who are directing it, have to know there will be a consequence, just as 20 years ago there was a consequence for those who slaughtered people in the Balkans.
"Ireland has taken a lead in a number of countries who are asking the United Nations to refer what is happening Syria to the International Criminal Court."
He said referring Syria to the ICC would ensure there would be an investigation and when the conflict was over, those responsible for the slaughter would be "brought to book".
Mr Gilmore said that as part of Ireland's presidency of the EU, the Government would continue to try to support the efforts of UN envoy Lakhdar Brahimi to broker a peace deal.
Senior US and Russian diplomats will meet Mr Brahimi in Geneva today to discuss the conflict.
They will review a plan first agreed last June for a ceasefire and the establishment of a transitional government.
However, President Assad made clear in a speech on Sunday that he had no intention of stepping down.