The Centre, in an affidavit, contended that legal validation of same-sex marriage will cause "complete havoc" with the delicate balance of personal laws in the country and in accepted societal values. Solicitor General Tushar Mehta, representing the Centre, stressed that legislative policy recognises marriage as a bond only between a biological man and a biological woman.

The Centre contended that it is for Parliament to decide whether same-sex marriage could be statutorily recognised.

A bench comprising Chief Justice D.Y. Chandrachud, justice P.S. Narasimha, and justice J.B. Pardiwala said it will invoke Article 145 (3) of the Constitution and have this matter decided by a constitution bench, comprising five judges. "It is a very seminal issue", said the bench, while fixing the matter for hearing on April 18.

The central government has told the Supreme Court that living together as partners and having sexual relationship by same sex individuals, which is decriminalised now, is not comparable with the Indian family unit - a husband, a wife, and children born out of the union - while opposing pleas seeking recognition of same-sex marriage. It stressed that same-sex marriage is not in conformity with societal morality and Indian ethos.

In an affidavit, the central government said the notion of marriage itself necessarily and inevitably presupposes a union between two persons of the opposite sex. This definition is socially, culturally, and legally ingrained into the very idea and concept of marriage and ought not to be disturbed or diluted by judicial interpretation, it added.

The affidavit said the institution of marriage and the family are important social institutions in India that provide for the security, support and companionship of members of society and bear an important role in the rearing of children and their mental and psychological upbringing also.

The Centre's response came on a batch of petitions challenging certain provisions of the Hindu Marriage Act, Foreign Marriage Act and the Special Marriage Act and other marriage laws as unconstitutional on the ground that they deny same sex couples the right to marry or alternatively to read these provisions broadly so as to include same sex marriage.