The openly gay Bishop of New Hampshire, whose consecration in 2003 has taken the Anglican Church to the brink of schism, is to be excluded from the Lambeth Conference next year.

The Archbishop of Canterbury said that Bishop Robinson would not be among the 800-plus Anglican bishops invited to Canterbury next summer. In a step that could risk a boycott from the Nigerian contingent, Dr Rowan Williams has also decided not to invite the Right Rev Martyn Minns, the evangelical bishop installed by the Church of Nigeria last year to serve orthodox Anglican congregations in the US.

Dr Williams sent out the first invitations for the three-week conference yesterday.

The gay community in the Church of England said that the decision demonstrated “institutional homophobia”.

But Dr Rowan Williams, once a proponent of liberal Catholicism of the kind preached by Bishop Robinson, had little choice. Had he invited Bishop Robinson, the conference would almost certainly have been boycotted by conservative evangelical bishops and archbishops from Africa and Asia.

The Lambeth Conference takes place every ten years and brings together bishops from the Churches in the 38 provinces of the Anglican Communion, plus other invited guests. The next gathering will differ from previous ones in that it will begin with a period of retreat and reflection.

The Archbishop’s wife, Jane, a theologian on the evangelical wing of the Church, will invite spouses later in the year.

In his invitation, Dr Williams says that the conference will be “an opportunity for all of us to strengthen our commitment to God’s mission and to our common life as a communion”.

He adds: “Because there has been quite a bit of speculation about invitations, I want to set out briefly what I think the conference is and is not.

“It is an occasion when the Archbishop of Canterbury exercises his privilege of calling his colleagues together, not to legislate but to discover and define something more about our common identity through prayer and shared reflection. It is an occasion to rediscover the reality of the Church itself as a worldwide community united by the call and grace of Christ.

“Coming to the Lambeth Conference does not commit you to accepting the position of others as necessarily a legitimate expression of Anglican doctrine and discipline, or to any action that would compromise your conscience or the integrity of your local Church.

“I have to reserve the right to withhold or withdraw invitations from bishops whose appointment, actions or manner of life have caused exceptionally serious division or scandal within the communion.” The Rev Martin Reynolds, of the Lesbian and Gay Christian Movement, said: “This is flagrant victimisation.” Bishop Robinson said that Dr Williams’s decision was a “great disappointment” and “an affront to the entire Episcopal Church”.