The Church of England has warned its clergy not to register same-sex relationships, following government confirmation that places of worship can host civil partnership ceremonies from next month.
Gay and lesbian couples can, from 5 December, celebrate their big day in religious premises opting into a new scheme. But there is no obligation on religious groups to take part in the initiative.
In a written statement the equalities minister Lynne Featherstone said: "The government is committed to removing the legal barrier to civil partnerships being registered on the religious premises of those faith groups who choose to allow this to happen."
The law currently bans civil partnership ceremonies on religious premises and the legal form of marriage is currently only available to opposite-sex couples.
But the Church of England has warned that its clergy should not provide services of blessing for same-sex couples.
A spokesman said: "We will study the draft regulations as a matter of urgency to check they deliver the firm assurances that have been given to us and others that the new arrangements will operate by way of denominational opt-in.
"If ministers have delivered what they said they would in terms of genuine religious freedom, we would have no reason to oppose the regulations. The House of Bishops' statement of July 2005 made it clear that the Church of England should not provide services of blessing for those who register civil partnerships and that remains the position. The Church of England has no intention of allowing civil partnerships to be registered in its churches."
A spokesman for the Catholic Bishops' Conference of England and Wales also reinforced its opposition to the new plans, saying the new provisions were unnecessary as none of its churches would be used for these purposes.
"As the regulations require prior consent, the measure can have no direct impact on Catholic premises. The church welcomes the fact that the government has made an explicit statement in the draft regulations that nothing in them creates any obligation to make an application for approval. This will help rebut any attempt to mount spurious cases of unlawful discrimination against churches which do not host civil partnerships."
Featherstone's announcement comes after an amendment was made in the last Parliament in the House of Lords to the Equality Act which removed the ban on holding civil partnership ceremonies in religious premises.
The Lord Alli amendment to the equality bill was passed in March 2010 by a majority of 74 votes.
Campaign group Stonewall welcomed the decision. Its chief executive, Ben Summerskill, said: "Since the first civil partnerships took place in 2005, religious groups and lesbian and gay people of faith have expressed the importance of being able to celebrate their commitment to one another in their place of worship. It is a clear signal of how far we've come that, for the first time, the many lesbian and gay couples of faith in Britain today will be able to do so."