Irish jihadis fighting for Isil and other terror groups should have their citizenship revoked, a senior Fianna Fáil TD has said.
Foreign Affairs spokesman Darragh O'Brien said "there should be no haven in Ireland" for people who fight for such organisations.
His remarks come amid a renewed focus on the Irish response to the threat of terror due to the revelation that one of the London attackers, Rachid Redouane, had lived in Dublin.
Mr O'Brien has accused the Government of being "complacent" about the likelihood of an attack here. His party colleague Willie O'Dea has also spoken of the need to deport people associated with terrorism.
Mr O'Brien said some countries did not allow citizens fighting for terror organisations to return from war-zones, citing Australia. It has begun stripping citizenship from dual-nationals fighting for Isil.
Mr O'Brien said several fighters had returned from wars in the Middle East, albeit some fought for rebel groups not linked to terror organisations.
He also referred to the case of Khalid Kelly, who died in a suicide attack in Iraq last year, saying he had been "hiding in plain sight" in Ireland espousing extremist ideology.
Mr O'Brien pointed out that the "vast bulk" of Ireland's Muslim population oppose extremist ideology as "an affront to Islam and an affront to any normal right-minded people".
He said there shouldn't just be a "big stick approach" and that there must be proper engagement with marginalised communities to make sure people don't become marginalised.
A spokesman for Justice Minister Frances Fitzgerald said the Government was "determined to do everything it can in the fight against terrorism and will continue to use all the powers available to it".
He insisted there was "no complacency", that the expert assessment was that "an attack here is possible, but unlikely", and that gardaí would continue to be supported with all the resources they needed.
Gardaí believe about 20 people have travelled from Ireland to fight in Iraq and Syria since 2011. Gardaí monitor and engage with people when they return to "assess the level of threat and they take all necessary measures in response to any threat".
The spokesman said there were provisions to revoke citizenship "in certain circumstances", including where evidence of terrorist activity is brought to the attention of the Justice Minister, who can invoke the process. He said it was "a complex matter which gives rise to considerable Constitutional issues as well as international considerations that must be taken into account".
Meanwhile, Royal United Services Institute (RUSI) security expert Raffaello Pantucci has said a terror attack in Ireland would most likely be targeted at a symbol of the US or UK like an embassy, rather than a London Bridge-style attack.
A British Embassy spokesperson said: "We always review our security, but we can't discuss that" while the US embassy said "we do not comment on security matters".