It also argued that those rights should be extended to unmarried couples without children if one of the ex-partners was at risk of suffering a substantial injustice when they separated.

Responding to recommendations from the Law Commission, the Church said it wanted to uphold the ideal of marriage but that there was a strong biblical precedent for protecting the vulnerable.

Its stance will dismay many Anglicans, who believe that any support for people living together outside marriage will erode the institution.

The Church's view also appeared to contradict comments by the Archbishop of Canterbury, Dr Rowan Williams. He said in June that the commission's proposals showed a proper concern for vulnerable people, but those anxious about the needs of a cohabiting partner could already make wills and draw up legal contracts. He said that marriage, which was the healthiest environment in which to bring up children, had "suffered a long process of erosion" and that the commission's proposals would further add to "a prevailing social muddle".

The Christian Institute, an influential lobby group, said: "Any change to the law that moves cohabitation on to a more equal footing with marriage is to be resisted.

"The danger with the Church of England suggestion is that any attempt to legislate on the dissolution of a cohabitation is likely to be further developed in the courts to reflect divorce law. That would further erode the special status of marriage."

The Church of England's stance also contrasts with that of the Roman Catholic Church, which issued a warning that the commission's proposals would "fundamentally change the legal basis of family life in this country".

The Catholic bishops said the courts should exercise some flexibility but added: "The real remedy for those who cohabit and are concerned about their rights is to get married. Couples who cohabit and deliberately choose not to marry forgo the responsibilities and obligations - and also the legal benefits - of marriage."

In the commission's consultation paper this year, it proposed a range of new rights for cohabiting couples in England and Wales who currently have a very limited entitlement to financial protection in the event of a split. Under its proposals, couples who have had a long-term relationship could be ordered to sell their home, pay lump sums to each other and share pensions if they go their separate ways.

The commission, which was asked by the Government to draw up the proposals, kept an open mind on whether cohabitants without children should be eligible. Final proposals and a draft Bill are expected next August.

Bishop Butler, who heads the Church's mission and public affairs council, said the General Synod had decided two years ago that there could be new legal rights for those in unmarried relationships.

"We recognise that society has a duty to protect children, whatever family structures they find themselves in," he said.

The Church was therefore "sympathetic to reform that addresses the effect of relationship breakdown on children and those who make sacrifices to care for them".

Bishop Butler said the Church rejected the idea that couples should be able to "opt in" to a new legal status for cohabitants or become eligible for the new rights on the basis of the length of their relationship, both of which could undermine marriage.

As a result, he said, the Church had concluded that eligibility should be based only on either having a child or on the ability to demonstrate manifest injustice.

END