Taoiseach Leo Varadkar has said Lisa Smith, who is being held in a Syrian refugee camp would "certainly" be investigated if she returns to Ireland.
Speaking to reporters this afternoon, Mr Varadkar said that Ms Smith has requested consular assistance however he said "we do need to bear in mind that were she is is a war zone and we don't want to put any of our diplomatic staff or officials at risk in any way."
He said that despite what people may think about what Lisa Smith has done "her child is innocent and her child is an Irish citizen and we will try to assist them.
"If she returns to Ireland, there will need to be an investigation into her activities certainly.
He said any security risk she may pose would have to be assessed but "the safety and interests of Irish citizens and people living in Ireland as the paramount concern in all of this.
"Should she return, she will be interviewed, there would be a security assessment done to make sure she is not a security threat to others.
"But we must never forget that there is a child involved here too and that child is innocent and that child is an Irish citizen."
He said she could "possibly" face criminal charges but that would have to follow an investigation but there is legislation regarding assisting terrorist groups.
It comes as Ms Smith told a BBC reporter that she wants "a caliphate as in a Muslim country", but not a "brutality group".
In an interview with BBC radio, Lisa Smith said she accepted there was a lot of brutality in the so-called Islamic State.
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However, she said she could not say if the perpetrators should be punished.
"I can't answer because I don't know". It is understood that Ms Smith, who is originally from Dundalk in Co Louth, travelled to Syria three years ago and now has a two-year-old child.
She is now being held at the Al Hawl refugee camp on the Syrian border with Iraq.
Ms Smith has previously served as a Private in the Irish Defence Forces, having joined at 19.
She also served in the Air Corps, working for a time on the Government jet.
In the interview, she denied she ever picked up a gun and said she was not allowed fight for IS and also denied training young girls to fight for the terror group.
Ms Smith said she could not explain why it had been alleged that she did train children to fight.
She said she was not a terrorist and was not "out to kill anyone".
She said she would not plan attacks in Ireland nor had any intentions to hurt anyone in Ireland.
She also said she did not think she was radicalised and simply "came to an Islamic State, and it failed".
Ms Smith said she did not travel to Syria to kill anyone, when she was there she did not kill anyone and if she returns to Ireland she said she will not kill anyone.
Minister for Employment and Social Affairs Regina Doherty said Ms Smith should be allowed back home from Syria.
Speaking to reporters, Ms Doherty said Ms Smith is an Irish citizen, and said she thinks she deserves consular assistance.
"I think she's an Irish citizen with a small baby, I think she should be allowed come home," she said.
She added: "If there are difficulties - I know there are concerns from some people that she may pose a security risk, but surely we can do a security assessment and deal with that."
"All I know is that she is a young woman with a small baby who feels very isolated and lonely where she is and I think she deserves consular assistance," she said.
At the time Mr Varadkar siad: "I am very conscious of the fact that while nobody can condone the choice that she has made and the actions that she took in aligning herself with ISIS, a terrorist regime that is hell-bent on the destruction of the west and Christendom, she does have a two-year-old child that is an Irish citizen and that child is an innocent child.
"And as is the case with all Irish citizens, they will be permitted to re-enter the State should they try to do so.
"But of course a security assessment will have to be carried out to make sure that Lisa Marie Smith is not a threat to any of us", he said.
Meanwhile, a former deputy director of Military Intelligence with the Defence Forces said he finds it difficult to believe Ms Smith's claim that IS did not know she was previously in the military.
Michael Murphy, who also runs security threat and risk management consultancy, said he believes she may be in denial about radicalisation.
"This is a person who left Ireland voluntarily, when everyone knew what this group were up to. Nobody in their right sense of mind who wasn't into this would have left Ireland to go and do this, so of course she's going to say she wasn't radicalised."
Speaking on RTE's News at One, he said IS carried out thorough investigations into people who were going to Syria, and he does not accept that they did not know Ms Smith was in the [Irish] military.
He also said the Government must learn a lesson from the situation, and that a law should have been in place many years ago to say that simply travelling to IS territory is a crime.