The appeal, being mulled over at Lambeth Palace, is expected to be the first of several. It represents the first formal step towards a schism that evangelicals say began with the consecration of the openly gay Gene Robinson as Bishop of New Hampshire in 2003.

The crisis was heightened as resolutions being debated over gays fell short of the "repentance" and "moratoria" demanded by the Windsor Report set up by Dr Williams. One well-placed conservative source said: "We are in uncharted waters. The Church is descending into anarchy."

Last night representatives of the Episcopal Church rejected suggestions that they broke with the worldwide Anglican Communion when they elected Bishop Robinson. In its first action, the 843-member House of Deputies rejected language expressing regret for "breaching the proper constraints of the bonds of affection" by his election. Instead, the deputies approved wording expressing regret merely for "straining" the bonds of affection with the Anglican Communion.

Dr Williams issued a guarded welcome to the new Presiding Bishop, referring to the difficulties the election represents for Anglicans. "I send my greetings to Bishop Katharine and she has my prayers and good wishes as she takes up a deeply demanding position at a critical time," he said. Bishop Schori will be instituted in November.

Bishop Schori told CNN yesterday that she did not believe homosexuality was a sin, adding: "I believe that God creates us with different gifts."

Fort Worth is one of three US dioceses not to accept women priests. These and a further seven evangelical dioceses belong to a network of orthodox parishes and dioceses that represent 10 per cent of the US Episcopal Church.

If Dr Williams agreed to provide alternative oversight and the entire American Anglican Network followed, there would be two Anglican Churches within the US. Both would be in communion with the Archbishop of Canterbury, although not with each other.

The crunch point would come at the 2008 Lambeth Conference, when both would be asked to sign up to a unifying "covenant" designed to prevent splits and actions in the future.

Officials at the US Episcopal Church have requested that it be known by its legal name of the Episcopal Church rather than the acronym ECUSA, as it represents 16 nations, not only the US. Speaking to The Times, Bishop Jack Iker, of Fort Worth, said: "We would like to be accountable to a bishop of the orthodox faith who shares our theology and perspective."

There was heated debate at the convention as resolutions on gay bishops came up for vote. The House of Deputies was due to take up a revised proposal that came close to calling for a moratorium on the consecration of gay bishops. Gay activists called that proposal "unacceptable".

THE SPLIT

1998 Lambeth Conference rejects homosexual practice as "incompatible with scripture" and advises against the "legitimising or blessing of same-sex unions" and of "ordaining those involved in same-gender unions"

2003 Vicky Imogene "Gene" Robinson, an openly gay father of two, is consecrated Bishop of New Hampshire. Archbishop of Canterbury sets up Lambeth Commission

2004 Commission publishes Windsor Report, which calls for repentance from US church and moratoria on future gay consecrations and same-sex blessings

2006 ECUSA, at its General Convention in Columbus, Ohio, decides that it will in future be known as the Episcopal Church, prompting theories that it is preparing to become an alternative, liberal Anglican Communion. Episcopal Church elects first woman, Bishop Katharine Jefferts Schori, as Presiding Bishop, equal in status to an archbishop. Delegates come close to fighting as they debate how far to go in complying with Windsor

2007 Archbishop of Canterbury will issue invitations to Lambeth Conference. He must decide whether or not to invite Bishop Robinson and any of the bishops who were consecrated. Bishop Schori voted for the election of Robinson but did not take part in his consecration

2008 Lambeth Conference will meet in the summer, when bishops and archbishops will agree either to "walk apart" or find a way of remaining in communion

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