The Government hopes to change the law to make it easier to convict people for membership of illegal organisations in the wake of the Omagh bomb which killed 28 people and injured hundreds.
The Attorney General will advise tomorrow's Cabinet meeting if this is legally possible.
The Garda Commissioner and RUC Chief Constable are to seek new ways of co-operating to combat cross-Border activity by dissident republicans. The Taoiseach and the British Prime Minister spoke on the phone last night.
The introduction of internment without trial is understood not to be under serious consideration at this stage, although neither government has ruled it out as a last resort. The Northern Secretary said it might only be necessary to deal with as few as 30 individuals, and warned against using "sledgehammer" tactics.
"The people who did this just aren't human, they are animals," Dr Mo Mowlam said yesterday. "I can assure you that we are going to leave no stone unturned. We are determined to do everything possible to ensure these people are taken off the streets."
She was speaking after a 3 1/2hour meeting with the Minister for Justice, Mr O'Donoghue, the Garda Commissioner, Mr Pat Byrne, and the Chief Constable, Mr Ronnie Flanagan. They met at Stormont to discuss the security response to the attack, assumed to have been carried out by the "Real IRA".
Five people from the Omagh region were still being questioned at Castlereagh holding centre in Belfast last night in connection with the bombing. Mr Francis Mackey, chairman of the 32 County Sovereignty Movement, which has been linked to the "Real IRA", confirmed yesterday that one of those arrested was his son Shane (19). He said his son was at work when the bomb went off, and again denied his organisation had anything to do with Saturday's atrocity.
"I am saying that I, and the 32 County Sovereignty Movement, is not involved in any military activity or involved in any way in what took place on Saturday," he said after an emergency meeting of Omagh District Council, of which he is a member.
Meanwhile, the political wing of the Irish National Liberation Army, the Irish Republican Socialist party, called on the INLA to announce a ceasefire.
Mr Ahern consulted several Ministers in Dublin yesterday to try to reach agreement in principle on radical measures to deal with dissident republicans ahead of the Cabinet meeting. Mr O'Donoghue indicated last night that what is being considered is an amendment to the Offences Against the State Act.
Government sources said last night the aim was to bring the situation regarding convictions for membership of illegal organisations back to the position that prevailed before 1976. Until then, the word of a Garda chief superintendent was enough to convict someone for membership of an illegal organisation. This offence carried a maximum sentence of two years.
However, when the sentence was increased to seven years in 1976, the courts took the view that corroboration of the chief superintendent's evidence was needed. Reversing this situation would raise complex legal issues, according to the sources, and so detailed advice from the Attorney General was required.
The Stormont meeting heard a long and detailed security briefing from the RUC Chief Constable and the Garda Commissioner. The ministers and their police chiefs then discussed security measures in three categories:
Enhancing practical security co-operation in the Border areas.
Making it easier to get convictions for membership of proscribed organisations.
Other measures, many with complicated legal dimensions that would go to the Taoiseach and Prime Minister for more detailed consideration.