President Michael D Higgins has urged people not to let terrorists believe they can strike fear into lives.
After signing a book of condolence in the Belgian embassy in Dublin, Mr Higgins condemned the attacks which left 34 dead and hundreds wounded as cowardly and useless.
“Like all terribly destructive acts of terrorism directed against civilians, it has no serious end purpose other than the creation of such fears as would dislodge people,” he said.
Mr Higgins expressed solidarity with the near 15,000 Irish people living in Belgium and said his thoughts were also with frontline workers who responded to the bombings.
“150 years of theory will tell you that these acts are desperate and hopeless and useless,” he said.
“They always create such fear as always creates the capacity for a reaction that would in effect not be entirely positive.
“These actions are terrible actions, they are cowardly actions … but it’s very important not to allow them to establish the fear which is their purpose.”
A minute’s silence was also observed at the embassy, with the book of condolence open to the public for several hours.
Mr Higgins called on people to demonstrate how they want to live in peace.
“At the end of the day the great response always to terror acts against civilians is that civilians have shown in their resilience that their values are more important,” he said.
“They are the values that endure from one generation to another.
“We reaffirm our commitment to wanting to live together in peace and being able to disagree in peace and none of this is associated frankly with any fundamental belief system or anything else.”
Meanwhile, Archbishop Eamon Martin has written to colleagues in Belgium to express solidarity and sympathies.
“The horrific loss of life and serious injuries caused by these senseless attacks undermines the fragile bonds upon which our peaceful co-existence as a society rests,” he said.
“I am mindful too of the work of security and healthcare personnel in offering assistance in a very difficult situation.”
