(CNN) -- Pope Benedict XVI is expected to meet the Archbishop of Canterbury on Saturday, the first meeting between the religious leaders since a Catholic overture to disaffected Anglicans that some commentators compared to a hostile takeover on Wall Street. Rowan Williams, the nominal head of the world Anglican Communion, threw down a theological gauntlet to the pope in a highly challenging speech in Rome in the run-up to their meeting. He laid out a series of questions suggesting that decades of hard-won apparent reconciliation between the Catholic Church and other Christian denominations might have weak foundations. He also proposed that a truly universal Christian church might have to be structured more like the Anglican Communion -- with no central authority laying down the law -- than like the Catholic Church, with the pope on his throne.
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Pope Benedict XVI, Anglican head to meet, discuss ideologies
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Vatican recently opened door to disillusioned Anglicans wanting to join Catholic Church
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Anglican Church has welcomed ordination of women, openly gay clergy
Anglican Communion
Anglican Communion
Anglican
Anglican Church
Williams was said to have been taken by surprise by the move, which critics described as an end run around a long-established Catholic-@placeholder dialogue.
Anglican Communion
Anglican Communion
Anglican
Anglican Church
Catholic and @placeholder theology and rites are broadly similar, but Anglicans have long allowed priests to marry and have children.
Rome
Pope Benedict hinted clearly when he last met Williams in Rome almost exactly three years ago to the day that @placeholder did not look kindly on the Anglican moves.
Anglicans
Anglicans
There are about 77 million @placeholder worldwide, and about 1.1 billion Roman Catholics.
Catholic Church
Catholic Church
Catholic Church
There are about 77 million Anglicans worldwide, and about 1.1 billion @placeholder.