In the most high-profile American defection to date in the row over gays in the Anglican Church, a diocesan bishop has explained why he is to be received into the Roman Catholic Church.

The Bishop of Rio Grande, Jeffrey Steenson, who was educated at Oxford and is in the Anglican Catholic tradition of the Church, said that to remain in his post in the Episcopal Church may lead him "to a place apart from Scripture and tradition”.

In a statement to American bishops meeting in New Orleans in an attempt to avert schism, in which he requested permission to resign both from his post and his orders, the Bishop Steenson said: “I am concerned that if I do not listen to and act in accordance with conscience now, it will become harder and harder to hear God’s voice.”

He said that he had already received counsel and prayers from the Presiding Bishop, the Right Rev Katharine Jefferts Schori. “Now I come before you, asking that you give me the necessary canonical permission to resign as ordinary of my diocese. I should like to do this by the end of this year, and afterwards, in proper order, to be released from my ordination vows in the Episcopal Church.”

His defection will come as a further blow to an Anglican province already reeling from the plans of up to five dioceses to seek leadership from a conservative province outside the US. Insiders say that the small but wealthy Episcopal Church, with about two-to-three million Sunday worshippers, is losing hundreds of people every year.

The row is ostensibly over the 2003 consecration of the openly gay Bishop Gene Robinson to New Hampshire, but in reality it is about the wider issue of Biblical interpretation and the place of tradition in a modern church in the secular world. The Church is about to be riven by litigation as many of the departing Episcopalians attempt to take their church buildings with them.

The Right Rev Steenson indicated that those who want to go should go quietly.

He said: “I hope my decision will encourage others who believe they can no longer remain in the Episcopal Church, to respect its laws and to withdraw as courteously as possible for the sake of the Christian witness.”

Referring to another meeting of the Church’s bishops this year, he said: “I was more than a little surprised when such a substantial majority declared the polity of the Episcopal Church to be primarily that of an autonomous and independent local church relating to the wider Anglican Communion by voluntary association. This is not the Anglicanism in which I was formed, inspired by the Oxford movement and the Catholic Revival in the Church of England. Perhaps something was defective in my education for ministry in the Episcopal Church, but, honestly, I did not recognise the church that this House described on that occasion.”

Committing himself to seeking unity with the Catholic Church, he accused the Episcopal Church of making a “decisive turn away” from efforts to preserve the communion. He said: “It is difficult to avoid the conclusion that the Episcopal Church has rejected the discipline of communion but wants it only on its own terms.”

He spoke as bishops in the US persevered in their attempts to save the Anglican Church from schism with a scheme to offer alternative oversight to traditionalist parishes that cannot accept the ministry of pro-gay bishops.

The scheme mirrors the “flying bishops” scheme that saved the Church of England froms schism by allowing traditionalist bishops to care for parishes that could not accept women priests after the General Synod voted to ordain them in 1992.

The scheme will not go far enough for some dioceses in the US.

The “message” of the US bishops will be published later today after nearly a week of tense discussions in New Orleans, including talks with the Archbishop of Canterbury, Dr Rowan Williams. It stops short of the schismatic and provocative act of defiance that was feared by many would result this week but will not go far enough to placate conservatives.

In an early draft of their message, the bishops emphasised that the US Church “needs the Anglican Communion” and acknowledged that their action in 2003 in consecrating the the Right Rev Robinson had caused “great difficulty for some in continuing effective mission and ministry in their own cultural contexts”.

However, they urged Dr Williams to invite the Right Rev Robinson to the 2008 Lambeth Conference, which he has not yet done, and urged him to appoint a group of bishops to find a way to include him.

They said: “We proclaim the Gospel that in Christ all God’s children, including gay and lesbian persons, are full and equal participants in the life of Christ’s Church.”