Anglican leaders want US and Canadian Churches to withdraw from the Anglican Consultative Council until 2008 because of their stance on homosexuality.
Rowan Williams warned the Church could split over gay bishops
The move comes after the US Church backed an openly gay bishop and same-sex unions began to be blessed in Canada in 2003.
Q: What is this row about?
The trigger is the disagreement over gay and lesbian Christians.
This came to a head when US Anglicans (their church is called the Episcopal Church of the USA, Ecusa) chose Gene Robinson, a gay priest who lives openly with another man, as bishop of New Hampshire.
The Canadian Anglicans also approved a service of blessing for same-sex unions.
Conservative and traditional Anglicans say this flouts the Bible's condemnation of homosexuality, while liberals and modernists (including the North Americans) say people should be free to live as God made them, gay or straight or whatever.
Dr Rowan Williams, the archbishop of Canterbury, set up a group of church leaders to try to end the crisis.
The meeting in Northern Ireland which called on the North Americans to stand down had been considering the group's findings, known as the Windsor report.
Underlying the row over homosexuality is a more basic struggle between the two camps.
Many conservatives say the Bible is an infallible guide to human conduct, which must be followed strictly.
The liberals say the Bible must be interpreted in the light of modern knowledge.
They also point out that some conservatives are selective in choosing which injunctions to obey: nobody now takes the Bible seriously on the treatment of slaves, for instance.
And Jesus himself is not on record as saying anything about homosexuality.
For years the different strands within Anglicanism managed to live together, respecting each other even when they disagreed strongly.
That was the peculiar Anglican genius - untidy, but effective and humane.
That tolerance is now giving way to a demand for orthodoxy which could mean a rigorously doctrinaire church.
Q: What is the Anglican Consultative Council?
It is a body of bishops,
priests and lay people from national Anglican churches who
meet and consult in between the once-a-decade Lambeth
It is one of the Anglican communion's four "instruments of unity", as they are called, the institutions which link the autonomous Anglican churches into a federation.
The others are the archbishop of Canterbury (the leader of the mother church), the regular meetings of primates (the senior bishops who head the communion's 38 provinces), and the Lambeth conference, the meeting every ten years of all Anglican bishops.
The ACC has no legislative powers, but provides a way for the different churches to act together.
Q: Why have US and Canadian Anglicans been asked to withdraw from it?
The conservatives wanted the North Americans to admit their error over homosexuality.
The apology the US made only expressed "sincere regret for the pain, the hurt and the damage caused ... by certain actions of our church".
The primates' statement at the end of their meeting in Northern Ireland said they were asking the US and Canadian churches to leave the ACC until the 2008 Lambeth conference "within the ambit of the issues discussed in the Windsor report and in order to recognise the integrity of all parties".
The request - or instruction - can be seen as a final offer to give time for repentance, or the final stage before a permanent split.
Q: When is the next Lambeth conference and what is it?
The next meeting will be in 2008, in Canterbury - hopes of holding it in South Africa have fallen through.
Each conference has to do several things - give more than 800 bishops (and their partners) a chance to get to know one another, offer time for reflection, study and prayer, and consider doctrine.
The 1998 conference's pronouncement on homosexuality still serves as a benchmark for many churches.
Q: What happens if the US and Canadian Anglicans don't voluntarily withdraw?
They could be turned back at the doors of the next ACC meeting, though Anglicans usually settle things more discreetly.
If the North Americans refuse to stand down, a final schism will happen sooner than in the three years the primates have offered.
But the likelihood is they will do as they've been asked.
Will it lead to a permanent split in the Anglican church?
Almost certainly yes.
There is no sign of either side giving way, and the proverbial Anglican genius for compromise and finding a form of words everyone can live with has virtually run out of steam.
Is the struggle being waged along racial lines, with the African churches taking a much more conservative line than the Europeans?
That's too simple a way of seeing it.
Certainly some African Anglicans are prominent in the traditional camp.
But so are others from Asia, South America and Australia, and also from the US and the UK.
One of the chief liberals is the archbishop of Cape Town, an African who says the church has far more urgent problems to talk about than sex.
In parts of Africa there is keen competition between Christians and Muslims, and that can strengthen the traditionalists' hand.
Probably part of the answer depends on who were the first Christian missionaries.
Much of central and west Africa was converted a century ago by conservative English Anglicans, while liberals were more active in southern Africa.