Vatican City - The Vatican set itself on a collision course with other Christian faiths Tuesday, reaffirming the primacy of the Roman Catholic Church in a corrective document which it said was designed to clear up recent "erroneous" doctrine.
The document's central claim, that only the Catholic Church is "the one true Church of Christ", is likely to revive a debate which has dogged the Vatican's relationship with rival Christian denominations for decades.
Such faiths, namely the Protestant and Orthodox churches, "lack elements considered essential to the Catholic Church," it said.
The document is the second strong reaffirmation of Benedict's traditional conservative line in the space of a few days. On Saturday, he issued a decree bringing back the old Latin mass alongside the modern liturgy.
The 16-page text -- released by the Vatican's doctrinal watchdog the Congregation for the Doctrine of the Faith, and ratified by the pope -- seeks to clear up "confusion and doubt" which has crept into the Church's relationship with other faiths.
It "constitutes a clear reaffirmation of Catholic doctrine on the Church," an attached commentary said.
Basically a restatement of bedrock Vatican doctrine contained in the controversial 2000 document "Dominus Iesus" -- introduced by then Cardinal Joseph Ratzinger -- the release of Tuesday's text was prompted "because some contemporary theological research has been erroneous or ambiguous," the Vatican said.
"Apart from dealing with certain unacceptable ideas which have unfortunately spread around the Catholic world, it offers valuable indications for the future of ecumenical dialogue," it said.
Benedict made unity with Protestant and Orthodox churches a priority of his pontificate in his first message as pope in April 2005.
"However, if such dialogue is to be truly constructive it must involve not just the mutual openness of the participants, but also fidelity to the identity of the Catholic faith," the document said.
Central to that identity is the idea that eastern or Orthodox churches were suffering a "wound" because they do not recognize the primacy of the pope.
It said "the wound is still more profound" in "communities emerging from the Reformation" -- the Protestant and Anglican churches.
These were "not Churches in the proper sense of the word", but rather "ecclesial communities", it said.
The Vatican acknowledged that this teaching had "created no little distress in the communities concerned" and recognised the "many elements of sanctification and truth" in other Christian denominations.
But only Catholicism could be seen as the one "Church of Christ", it said, adding that it was "difficult to see how the title of Church could possibly be attributed" to them.
It said the 1962-65 Second Vatican Council, which was aimed at opening up to non-Catholic christians, "did not intend to change, and therefore had not changed, the previously-held doctrine of the Church".
However, "erroneous interpretations at variance with traditional Catholic doctrine" had crept into Church teaching in the four decades since the Council, it said.
Ratzinger, who became pope in 2005, was a theological consultant at the council, and Tuesday's document was immediately seen by one Catholic prelate, who wished to remain anonymous, as espousing a "restrictive" view of the council.