Ireland is to hold a referendum in the spring to allow gay marriage, in the most significant move in 20 years to change the law to reflect a changing social environment.

Voters will be asked in May to approve an amendment to the constitution that reads: “Marriage may be contracted in accordance with law by two persons without distinction as to their sex.”

The campaign will be a test of the public standing of the Catholic church as it struggles to reassert its authority in the wake of clerical child sexual abuse scandals that ravaged the institution in recent years. The church is expected to play a part in the campaign against adopting the constitutional amendment, but may not want to be seen to lead it.

The position of gay people in Ireland has shot to the top of the political and social agenda after Leo Varadkar, the health minister, became the first serving member of an Irish government to announce that he was gay. His announcement on a radio talk show last weekend has been acclaimed by much of the public and by fellow politicians.

Ireland has been transformed in recent years from one of Europe’s most socially conservative countries, where the church held enormous public influence. The change coincided with a surge in wealth, economic growth and immigration, and the trend has not been halted despite the economic crash and austerity of the past few years.

Homosexual relations were legalised in 1993, while civil partnerships were introduced in 2010. A constitutional ban on divorce was lifted in 1993 in a referendum. At least some of the pressure for more progressive social legislation came from the European Court of Human Rights, which frequently ruled against the Irish state on issues of civil and human rights.

Announcing the wording of the marriage equality referendum on Wednesday, Frances Fitzgerald, the justice minister, said: “It is about removing the barriers which deny some couples the chance of marrying and of having relationships that are constitutionally protected.”

Kieran Rose, chairman of the Gay and Lesbian Equality Network, said: “The referendum, if carried, will complete the remarkable 25-year journey to constitutional equality for lesbian and gay people in Ireland.”

Support for gay marriage among the Irish public is nominally strong. It is also backed by a swath of political and media opinion.

An opinion poll in the Irish Times in December suggested that more than 70 per cent of voters would approve the constitutional change.

However, the issue has become embroiled in a separate move by the government to make it easier for people — including gay people — to adopt children, which has aroused strong opposition from conservative groups, and which is likely to feature prominently in the campaign against the amendment.

Financial Times