The Cabinet has agreed to hold a referendum on same-sex marriage sometime in the lifetime of the Government.

The move comes in the wake of the decision by the Constitutional Convention in April to recommend that the Constitution be amended to allow for same-sex marriage.

Minister for Justice Alan Shatter brought a memo to Cabinet this morning on the issue of civil marriage for same-sex couples, RTE reports.

Meanwhile, the Iona Institute has said that the debate over same-sex marriage “is really about the value we attach to motherhood and fatherhood and the natural ties”.

In a statement, they rejected the suggestion that the debate was about equality, saying that it was “no breach of the equality principle to treat different situations differently”.

“The sexual union of a man and a woman is unique and warrants a unique social institution,” the statement said.

The statement continued: “Changing marriage to accommodate same-sex couples treats all of them as unimportant or outright denies them.

“For example, same-sex marriage advocates insist that the roles of mothers and fathers are not complementary and say the natural ties can be deliberately broken.”

Commenting on the cabinet decision, the Iona Institute’s Dr John Murray said: “This debate is really about the value we attach to a child having a mother and a father as distinct from two fathers or two mothers. Do we think having the love of a mother and a father confers any special advantage on children or not? Do we think the natural ties between children and their parents matter at all?

“If we redefine marriage, we will be saying as a society that these things don’t matter. We will also be saying that the sexual union of a man and a woman isn’t different in any socially significant way from that of two men or two women. Given that only the former can result in children, this is plainly untrue. Different things should be treated in different ways. This does not violate the principle of equality.”

He continued: “Marriage does not need to be redefined in order to take care of children raised in other family forms. The rights of gay couples, and other people in caring relationships can also be taken care of without redefining marriage. Many of them have already through partnership rights.

“Redefining marriage is ultimately an attack on the natural rights of children. It is a step we should not take, especially by a Government that claims to be in favour of children’s rights.”