An Irish bishop says same-sex relationships can never be seen as “equal” to heterosexual relationships.

Christopher Jones is the chairman of the Catholic bishops’ Council for Marriage and the Family.

Mr Jones said he would welcome the opportunity to make an oral submission on same-sex marriage to the Irish Convention on the Constitution.

The convention is examining equal marriage, along with other key issues, in a year-long consultation exercise.

According to the Irish Times, Mr Jones warned that marriage was at risk of being attacked in Ireland.

In a written submission to the convention he said: “attempts to equate same-sex unions with marriage will always ultimately fail because it is objectively impossible for homosexual couples to achieve the same natural end toward which the sexual complementarity of male and female is ordered.”

He continued: “Therefore, were society to treat same-sex relationships and marriage as the same and therefore ‘equal’ would be to suggest that same-sex unions can be something that they are not.”

“Any change to the definition of marriage would create great difficulties,” he said, “and in the light of this if there were two totally different definitions of marriage the church could no longer carry out the civil element.”

Mr Jones spoke of their being a “potential impact” on the relationship between the “family and the State, notably in relation to the rights of children”.

Meanwhile, the Church of Ireland Changing Attitude Ireland (CAI) group has strongly supported the extension of civil marriage to same-sex couples, in its submission to the convention.