THE Labour Party has criticised the Government's decision to prevent the Church of England from opting in to conduct same-sex marriages.

Yvette Cooper, the Shadow Home Secretary, said on Tuesday that the Government was "rowing back on equal marriage. . .

"The Government is right to say that no church should be required to hold same-sex marriages. But freedom of religion goes both ways. Churches that want to show they treat all loving couples equally should be able to do so."

The Prime Minister indicated last Friday that the Government would legislate to allow churches in England and Wales to conduct same-sex marriage ceremonies. It had previously said that religious groups would be unaffected by the proposals because they applied to "civil marriage" and not "religious marriage" (News, 15 June).

Mr Cameron said that there would be a free vote among Coalition MPs on the Bill. Reports suggested that the Leader of the Opposition, Ed Miliband, would also give Labour MPs a free vote.

The Coalition for Equal Marriage has estimated that seven Labour MPs will vote against the legislation. Opposition on the Conservative backbenches will be much stronger: it is thought that as many as 100 Conservative MPs are likely to vote against.

During questions to the Equalities Minister, Maria Miller, in the House of Commons, on Monday, a number of Conservative backbenchers denounced the plans to introduce same-sex marriage.

Bob Stewart, the Conservative MP for Beckenham, asked why the Government was "so hell-bent on upsetting so many thousands of our citizens who are in normal marriages".

Dr Matthew Offord, the Conservative MP for Hendon, asked whether the Government had "considered introducing other forms of marriage, such as polygamy". Mrs Miller responded that the law was "clear" that "marriage is between two people."

Another Conservative MP, Brian Binley, a practising Anglican, wrote an open letter to Mr Cameron, on Tuesday, saying that "countless activists" were "feeling driven to give up their much-needed support for the party". As the gay-marriage legislation progresses, "this injury can only get worse," he wrote .

A book, Is There a Case for Same-Sex Marriage?, published by Anglican Mainstream, was last week mailed to every member of the House of Commons and the House of Lords. Canon Chris Sugden, of Anglican Mainstream, said that he hoped that the book would "strengthen the Tory grassroots' opposition" to the Government's proposals.

A poll published on Wednesday by YouGov suggested that Conservative voters were divided on the issue of gay marriage. Of the 1726 adults polled who were Conservative voters, 46 per cent indicated that they were in favour, and 48 per cent were opposed to gay marriage. Fifty-five per cent of those polled overall supported changing the law to allow same-sex marriage.