Pope says Vatican will excommunicate women priests

The decree, published in the Vatican newspaper L'Osservatore Romano, makes the Church's existing ban on women priests more explicit by clarifying that excommunication would follow all such ordinations.

People excommunicated from the Catholic Church are forbidden from receiving the sacraments or sharing in acts of public worship.

Rev. Tom Reese, a senior fellow at the Woodstock Theological Center at Georgetown University, said he thought the decree was meant to send a warning to the growing number of Catholics who favour admitting women to the priesthood.

"I think the reason they're doing this is that they've realised there is more and more support among Catholics for ordaining women, and they want to make clear that this is a no-no," Mr Reese said.

The Church says it cannot change the rules banning women from the priesthood because Christ chose only men as his apostles. Catholic law states that only a baptised male can be made a priest.

But advocates of women's ordination say Christ was only acting according to the social norms of his time.

They cite the letters of Saint Paul, some of the earliest texts of Christianity, to show that women played important roles in the early church.