The head of the Catholic Church in Ireland warned the Irish Government on Tuesday not to pass legislation giving the same rights to cohabiting couples as married couples.

Cardinal Sean Brady told delegates at the 11th annual Ceifin Conference in Co Clare that the legislation had the potential to "undermine God's will for marriage and the family".

The Word of God was, he reminded delegates, "pro-love, pro-marriage, pro-family, pro-life and pro-society".

He added that Ireland would be repeating the mistakes of Britain and the US if it introduced legislation giving equal status to cohabiting and married couples.

The Cardinal pointed to research which suggests that children born outside of marriage are more likely to do worse at school, suffer poorer health and face problems of unemployment, drugs and crime, than the children of a married couple.

"All the more remarkable then that Ireland looks set to repeat the mistakes of societies like Britain and the US by introducing legislation which will promote cohabitation, remove most incentives to marry and grant same-sex couples the same rights as marriage in all but adoption," he said.

Cardinal Brady argued that marriage and the family were "fundamental to the public good" and therefore "entitled to special consideration and care from the state".

"Other relationships whether they are sexual or not, are the result of private interest. They do not have the same fundamental relationship to the good of society and to the bringing up of children as the family based on marriage," he said.

Cardinal Brady called for more support for traditional marriage between a man and a woman, including positive incentives to encourage couples to marry.

Marriage has become an issue of contention in Ireland since the Government published legislation in June on the registration of same-sex and cohabiting couples.

The Cardinal warned that supporters of traditional marriage "may have to pursue all avenues of legal and democratic challenge to the published legislation".