The Archbishop of Southwark, the Most Rev Peter Smith, has claimed it is not “necessary nor desirable” for gay couples to have civil partnerships conducted in churches and other religious buildings.

In a statement, he goes on to claim that the government are on course to make a “fundamental change to the status of marriage”.

The archbishop’s statement comes a week after the coalition government announced the process for allowing gay couples to hold their civil partnerships in religious buildings.

It was also announced that a consultation will begin on the introduction of same-sex marriages and opening civil partnerships up to heterosexual couples, measures that PinkNews.co.uk understands both David Cameron and the deputy prime minister, Nick Clegg are in favour of.

While the Quakers and Unitarians together with both Liberal and Reform Judaism have said they will not only welcome civil partnership ceremonies but advocate full same sex marriage, the Church of England and the Catholic Church are opposed to the plans.

The plans are permissive and do not force any church or other religious institution to hold same sex ceremonies.

In addition, equality minister Lynne Featherstone said last week that no church minister would be successfully sued for refusing gay couples ceremonies.

Today, the archbishop claimed that the changes were “never envisaged by the Equality Act or any other legislation passed by parliament”.

Last year, the House of Lords adopted an amendment tabled by the Labour peer, Lord Waheed Alli to allow gay couples to hold ceremonies within religious buildings.

In a dig at both politicians and the faith groups that wish to hold same sex ceremonies, the archbishop wrote: “No authority – civil or religious – has the power to modify the fundamental nature of marriage.

“The Equality Act was amended to permit civil partnerships on religious premises, which unhelpfully blurs the distinction previously upheld by parliament and the courts between marriage and civil partnerships.

“A consenting minister is perfectly free to hold a religious ceremony either before or after a civil partnership. That is a matter of religious freedom, but it requires no legislation by the state. We do not believe it is either necessary or desirable to allow the registration of civil partnerships on religious premises. These will not take place in Catholic churches.”

The archbishop added: “Marriage does not belong to the state any more than it belongs to the church. It is a fundamental human institution rooted in human nature itself. It is a lifelong commitment of a man and a woman to each other, publicly entered into, for their mutual wellbeing and for the procreation and upbringing of children.”