Pope Benedict XVI on Monday denounced laws giving legal recognition to gay and unmarried couples, saying such legislation dramatically subverted the God-given institute of marriage.
Benedict's warning came a few days after the Italian government approved a draft law which recognises relations between cohabiting gays and unmarried heterosexual couples, granting rights in areas like inheritance and health care.
"No man-made law can subvert one made by the Creator without society being dramatically damaged in its very foundation," the pope said.
Although he made no specific reference to the bill approved by the centre-left government last Thursday, the pope said such legislation goes against natural laws, "weakens the family and penalises children."
The bill, which must still be approved by parliament, was a compromise between left-wingers in the government and Catholic-oriented centrists.
But it has already stirred up a hornet's nest in the country and in both the opposition and government ranks.
Justice Minister Clemente Mastella, head of the centrist Udeur party, deserted the cabinet meeting which approved the bill.
Opposition and centrist Catholic MPs have denounced it as a first step to the introduction of same-sex marriage in Italy while leftists and gays say it does not go far enough.
So far, however, the strongest opposition has come from the Catholic Church, which still holds considerable influence in Italian politics.
The head of the Italian Bishops Conference (CEI), Cardinal Camillo Ruini, weighed into the debate on Monday, saying that the church was preparing a document which would spell out the stance Catholics should take on the issue.
He said the document could be "important because it would provide a meditated stance - an official view - which would bind those who follow the Church's teachings and would offer clarification to others."
Ruini's statement sparked an immediate reaction, with centre-right MPs hailing his intervention and leftists railing against it.
The leader of the gay rights lobby group Arcigay Aurelio Mancuso blasted Ruini for presuming he was "the State's guardian."
"As can be expected, Italian politicians will pledge obedience," Mancuso said.
Arcigay founder and gay MP Franco Grillini said the "pope and Ruini were lying."
He said Italy was at "risk of (falling under) a clerical dictatorship."
GOVERNMENT WILL NOT CALL FOR A CONFIDENCE VOTE ON BILL.
The government's proposals, referred to as DICO (Diritti di coppie conviventi - Rights for cohabiting couples), falls short of the civil unions introduced in France, Britain and Spain in recent years.
Gay rights campaigners and hard leftists in Prodi's coalition wanted a more far-reaching measure, akin to the PACS (Civil Solidarity Pacts) legislation in France.
The DICO bill would give cohabiting partners inheritance rights after nine years of living together and alimony rights after three.
If specific provision was made beforehand, it would also allow one partner in a couple to take decisions on funeral arrangements and organ donation when the other died.
The bill could be modified when it goes to parliament in coming weeks. The centre-right opposition has promised a battle and several centre-left MPs have talked about "improvements".
the government has said it will not call a do-or-die confidence vote on the bill in order to force possible dissenters into line.
Although the coalition led by Premier Romano Prodi has only a razor-thin majority in the Senate, the bill is expected to have the support of some centre-right senators whose votes could compensate for defections in the centre left.