The Taoiseach, Mr Ahern, has condemned the bomb attacks in the Spanish captial Madrid this morning, describing them as an "atrocity".
"The timing of the bombings was clearly designed to wreak the greatest level of havoc and carnage," he said. They are an attack on the democratic process and cannot be justified by any political cause."
President Mary McAleese sent her sympathies to King Juan Carlos of Spain and the Spanish ambassador in Dublin. She described the blasts as "a terrible loss of innocent life".
The Tánaiste and Minister for Enterprise, Trade and Employment, Ms Harney expressed her deepest sympathy to the Spanish Government and its people on behalf of the Irish Presidency.
Ms Harney, presiding at a meeting of Competitiveness Council Ministers in Brussels said: "We in Ireland know only too well the devastation that is perpetrated by terrorist atrocities and we empathise with the pain and suffering being felt by the Spanish people at this time." She called for a minute's silence before the meeting as a mark of respect for the victims.
The Minister for Foreign Affairs, Mr Cowen, expressed his "horror and revulsion" at the bomb attacks. "I condemn in the strongest terms those responsible for this morning's bomb attacks in Madrid," Mr Cowen said.
"Horror and revulsion are the words that come to mind. As we have learned here in Ireland, violence has no place in the political process."
Mr Cowen said he had spoken with Spain's Foreign Minister, Ms Ana de Palacio, to convey his sympathies and those of the Irish people.
"My thoughts are with the families and friends of those killed in the attacks. I firmly believe that there can be no excuse, no justification for such actions," he added.
A spokesman for Department of Foreign Affairs said there were no reports as yet of Irish fatalities or injuries. "But we are in constant contact with our embassy," the spokesman said.
Mr Pat Cox, President Of The European Parliament, said it was "the worst act of terror in the history of Spain and the worst act of terror in memory in any European Union state. There shall be no safe haven for terrorism and terrorists in our European Union."
Fine Gael Leader, Mr Enda Kenny, said the bombings were "an attack on democracy itself coming just three days before the Spanish general election."
Labour Party leader, Mr Pat Rabbitte, said described this morning's attacks as "a despicable crime that will horrify anyone with any shred of decency or humanity."
"These were murderous attacks aimed not just at the Spanish people but also at Spanish democracy itself," he added.
The Green Party spokesman on foreign affairs, Mr John Gormley, conveyed his deepest sympathy to the people of Spain for the "an act of barbarism".
Sinn Féin president Mr Gerry Adams condemned the bomb attacks as "an appalling act".
"It is wrong and those involved should stop. Like everyone else I have been horrified by the images of this mornings atrocity and my thoughts and prayers are with the bereaved families and those who have been injured," he said.