Efforts by politicians to make priests violate their obligation to keep secret what they hear in confession are "unacceptable", the Vatican says.
The Vatican has reaffirmed the Catholic teaching that priests cannot reveal what they learn in confession, in an apparent response to moves in Australia and elsewhere to force them to do so in cases of sexual abuse.
A document from the Vatican's Apostolic Penitentiary, which deals with issues of the sacrament of confession, said no government or law could force clergy to violate the seal "because this duty comes directly from God".
The document, which did not mention any countries or the sexual abuse crisis, complained of a "worrying negative prejudice against the Catholic Church".
Most countries' legal systems recognise the right of a Catholic priest not to reveal what he has learned in confession, similar to lawyer-client privilege.
But the sexual abuse crisis that has embroiled the Catholic Church around the world has seen this right challenged more frequently.
Australia's royal commission into institutional responses to child abuse recommended a law forcing religious leaders to report abuse, including priests told of it during confession.
So far, two jurisdictions - South Australia and the Northern Territory - have introduced laws making it a crime for priests to withhold information about abuse heard in confession.
Western Australia has moved to introduce the laws and other jurisdictions are still considering their response.
In May, the California state senate passed a bill to require the seal of confession to be broken if a priests learns of or suspects sexual abuse while hearing the confession of a fellow priest or a colleague such as a Church worker.
Church leaders in both the US and Australia have opposed such laws and the Vatican document backed them up unequivocally.
"Any political action or legislative initiative aimed at breaking the inviolability of the sacramental seal would constitute an unacceptable offence against the (freedom of the Church)," the document said.
"(The Church) does not receive its legitimacy from individual States, but from God; it (breaking the seal) would also constitute a violation of religious freedom, legally fundamental to all other freedoms, including the freedom of conscience of individual citizens, both penitents and confessors," it said.
Victims advocates said the lifting of the seal of confession, even partially, was drastic but necessary under the circumstances.