By Simon Walters -Gays and lesbians will be able to 'marry' in church under new laws to be unveiled this week.
The historic decision by Liberal Democrat Equalities Minister Lynne Featherstone will end the legal definition of marriage as a relationship between a man and a woman.
A gay couple will be able to refer to one of the partners as a 'husband', and a lesbian couple will be able to refer to one of the partners as a 'wife'.
A key part of the reform will bring an end to the ban that prevents civil partnerships being conducted in places of worship.
Proposal: Sir Elton John and David Furnish at their civil partnership at the
Guildhall in Windsor in 2005. Under proposed changes, they could hold
the ceremony in a church.
The measure received a warm welcome last night from equalities groups but it could face opposition from Right-wing Tories and some Christian groups.
Archbishop of York Dr John Sentamu today warned against allowing one set of rights to 'trump' another.
He told the BBC: 'I, who believes in a liberal democracy, and actually wants equality with everybody, cannot say 'the Quakers should not do it' nor do I want somebody to tell me 'but the church of England must do it, but the Roman Catholic church must do it' because actually that's not what equality is about. You mustn't have rights that trump other rights.'
Amendment: Equalities Minister Lynne Featherstone proposes to lift the ban on civil partnerships in religious venues
But many gay people regard them as a second-class option and have campaigned to be granted the same legal and symbolic status as other marriages.
Ms Featherstone will also say gays should be able to hold traditional weddings in register offices and other civil settings such as country houses and even football grounds.
The move could lead to a clash between the State and the church.
The Church of England has already said it will not let its buildings be used for civil partnership ceremonies.
The Roman Catholic Church takes an even tougher line - Pope Benedict last year described same-sex marriage as being among 'the most insidious and dangerous challenges that today confront the common good'.
Both the Catholic Church and Islam say marriage can consist only of a union between a man and a woman.
But some faiths are in favour of a change in the law. The Quakers, Unitarians and Liberal Jews are expected to apply for permission to use their buildings to host same-sex marriages.
The change could also lead to legal action by gay couples denied the right to marry in church.
Gay marriages are already legal in Canada, South Africa, Sweden, Spain, the Netherlands and some American states.