Attorney General Séamus Woulfe advised the Government that if the electorate was asked to simply repeal the Eighth Amendment, it might be argued subsequently before the courts that the unborn has rights under other articles in the Constitution.
In a document containing a summary of his advice seen by RTÉ News, it states this could continue to restrict the Oireachtas to legislate on the matter.
Last night, the Cabinet formally agreed that voters should be asked whether or not to repeal the Eighth Amendment and also to replace it with new wording to be put into the constitution that the Oireachtas should legislate on this issue.
This decision was made after Cabinet was briefed on the matter by the Attorney General.
The preference is for the referendum to take place in late May, but this will be dependent on the passage of the bill to hold a referendum through the Oireachtas.
The document states that Mr Woulfe advised that wording should be added to the constitution expressly affirming the right of the Oireachtas to legislate for the regulation of termination of pregnancy.
The legal advice states it would bring greater constitutional certainty to the primary authority of the Oireachtas to make laws in this area.
It also states it would not oust the judicial review jurisdiction of the courts or restrict rights of access to the courts.
The legal advice also states that legislation passed after the referendum would remain subject to review by the courts like any other legislation.
New - summary of advice given to the Cabinet by the AG @rtenews pic.twitter.com/u6m0bv8m6q— Martina Fitzgerald (@MartinaFitzg) January 30, 2018
It comes after Taoiseach Leo Varadkar urged politicians not to become embroiled in disrespectful or personalised attacks during the referendum.
"It should be respectful of all sides and it should never be personalised," the Taoiseach said in the Dáil.
"Even when people are not being respectful or are personalised towards us we should not respond."
Mr Varadkar added that: "This is now a matter for the Irish people. It is in their hands.
"I think it is right that Irish people should be asked this question.
"When it was last asked I was four-years-old. Nobody under 52 has had a vote on this issue. I think it's appropriate that people should be allowed to have this vote."
Both Labour and Sinn Féin have said they want to see the Attorney General's advice in full.
Speaking in the Dáil, Sinn Féin health spokesperson Louise O'Reilly called on the Taoiseach to commit to publishing the advice fully, saying it was necessary for all politicians and the general public to be fully informed on the matter.
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Mr Harris has said he will draft legislation around the recommendations made by the Oireachtas Committee on the repeal of the Eighth Amendment.
He said he will publish a general scheme of that legislation by the end of March or the beginning of April.
He added that he intends to go back to Cabinet at the end of February to update it on his thinking and will also provide a further update to the public at that time.
Speaking on RTÉ's Morning Ireland, he said: "Whether the Eighth Amendment is in our Constitution, or indeed not in our Constitution, abortion is a reality for Irish women.
Mr Harris said he cannot close his eyes to the fact that 3,265 citizens travelled to the UK in 2016 from across Ireland.
"I cannot stand over a situation where the abortion pill is illegally accessed in this country and women, perhaps in the privacy of their own bedroom, in a lonely isolated place, [are] taking a pill without any medical supervision."
The minister said that as a result of the committee's recommendations, the legislation will include provision for abortion without restriction for 12 weeks.
He said the proposed legislation would also provide for abortion in the case of "fatal foetal abnormality", and in the cases of women's health but not in cases of disability.
Several ministers, including Tánaiste Simon Coveney, have raised concerns about proposals that terminations should be allowed unrestricted up to 12 weeks. at the meeting.
Mr Coveney said: "The status quo of how women are treated in crisis pregnancy cannot remain. I am united with my Cabinet colleagues in agreeing to repeal the Eighth Amendment and allow enabling legislation.
"While there are differing viewpoints on the content of that legislation, particularly on 12 weeks' access unrestricted, that is a matter for the Oireachtas to now debate.
"My views are clear on that and I expressed them at Cabinet."
@campaignforleo says 'we cannot continue to export our problems and import our solutions' on abortion pic.twitter.com/1ElwLfbJvf— RTÉ News (@rtenews) January 29, 2018
Diversity of opinions at Cabinet meeting - Madigan
Minister for Culture, Heritage and the Gaeltacht Josepha Madigan said she expects that ministers will be speaking and campaigning on both sides of the referendum campaign.
She said that the decision to hold a referendum was unanimous but also said there was a diversity of opinions around the Cabinet table.
Ms Madigan said she personally hopes the referendum is passed and supports the proposal for unrestricted access up to 12 weeks and also of the enabling clause as advised by the Attorney General.
Separately, speaking on RTÉ's Morning Ireland Fianna Fáil TD for Waterford Mary Butler said she supports a referendum and that the people should have their say.
She said that she was against repealing the Eighth Amendment and would not support unrestricted abortion, but that her opinion would differ to that of other people.
Ms Butler said that this was an emotive and decisive issue and it was up to each Irish person to decide how they wanted to vote.
"This is a hugely emotive, decisive, a hugely emotional and personal issue. But I believe it's up to every single Irish person to look into their own conscience and to decide which way they want to vote," she said.
The Waterford TD said that the issue was dependent on Dáil arithmetic and there were conflicting views on the issue in the Dáil.
Fine Gael TD Kate O'Connell said there is abortion in Ireland already, but it is illegal and the purchase of almost 2,000 abortion pill from unregulated sources online is a source of concern.
Speaking on RTÉ's Today with Sean O'Rourke, the Dublin Bay South TD said her party does not feel the status quo can continue and something must be done for the women of Ireland.
Independent TD Mattie McGrath said repealing the amendment is an effort to "open the door" to a lucrative industry and that efforts should be made to support women in crisis and unwanted pregnancies.
He said he would like perinatal hospices to be set up to help those parents who are told their child has a life-limiting condition.
Following a meeting with Mr Harris, Solidarity/People Before Profit TDs criticised the timeline for the passing of the bill.
Bríd Smith said that an "inordinate length of time" is being used to publish the bill, and called for it to be done before 8 March – International Women’s Day.
The @labour party say they want to see the AG's legal advice to the cabinet on what question should be put to the people in the referendum on the #8thAmendment @rtenews pic.twitter.com/QrWZxw9d6Z— Martina Fitzgerald (@MartinaFitzg) January 30, 2018