President Michael D Higgins has signed off on new laws governing the asylum application process, a day after convening the Council of State.
Mr Higgins opted against referring the International Protection Bill 2015 to the Supreme Court despite having expressed concerns that elements of it might be "repugnant" to the Constitution.
A three-hour meeting of the Council, which includes current and former Taoisigh and presidents, took place on Tuesday.
The President then took a further 24 hours to consider the Bill.
It is understood that Mr Higgins' concerns centred on the definition of the family in the Bill - however a majority of the Council of State felt it was within the scope of the Constitution.
The legislation allows for less discretion on the part of ministers for justice in deciding whether extended family members can travel to Ireland to live with people who have been granted asylum.
The Government rushed it through the Dáil and Seanad in the advance of the Christmas break.
In a statement last night, Áras an Uachtarain said: "In accordance with the terms of the Constitution, President Michael D. Higgins has today, 30 December, signed the International Protection Bill 2015 into law."
Mr Higgins has had a busy Christmas period after the Government sought to rush a series of legislation through the Dáil before their own recess.
The President also signed the Assisted Decision-Making (Capacity) Bill 2013 and the much publicised Legal Services Regulation Bill 2011 into law yesterday.
Inclusion Ireland welcomed what it described as the "historical enactment" of the assisted decision-making laws, saying they would change the lives of people with intellectual disabilities.
It brings about the long-awaited repeal of the Lunacy Regulation (Ireland) Act 1871 and the Marriage of Lunatics Act 1811.
In a statement, Inclusion Ireland said the change of law "demonstrates a seismic cultural shift".
Its chairperson Tom Healy said: "This modern legislation is a huge step forward and it means that persons with intellectual disabilities will finally have their ability to make decisions for themselves recognised in law."
He said the delay in the enactment of the legislation was one reason repeatedly given by the State for its failure to ratify the UN Convention on the Rights of Persons with Disabilities and the Government should now ratify it.