The Fine Gael leader, Mr John Bruton, has said those responsible for the bombing "are addicted to violence and have no place in a civilised society".
He called on the Taoiseach to instruct the Minister for Justice to meet immediately with the Northern Secretary to co-ordinate an all-Ireland security initiative which would make the commission of such outrages impossible. "The scale of the Omagh bomb shows the dangers of weaponry of this calibre remaining in private hands, outside the control of democratic state authorities."
The Labour party leader, Mr Ruairi Quinn, indicated his party's support for the vigorous pursuit of those responsible. He said the bombing was designed to subvert the peace process which had been supported by the vast majority of people on the island. "Today's attack is the work of fascists determined to upset the democratically-expressed will of the people."
The Democratic Left leader, Mr Proinsias De Rossa, said no cause could be advanced by the slaughter and maiming of innocent people about their legitimate business in a busy town centre.
The Sinn Fein TD for Cavan-Monaghan, Mr Caoimhghin O Caolain, said he utterly deplored the bombing and extended deepest sympathies to the bereaved and injured.
A Green Party spokesman, Mr Dan Boyle, said while every effort must be made to bring people to account for "this evil crime", there must be a resolute pursuit of the peace process as the only viable option.
