Pope John Paul condemned gay marriages today by saying laws that allow them promote an "unnatural vision" of man and pose a direct challenge to the family as the "very sanctuary of life".
The Pope included his attack on gay marriages in a yearly address to diplomats informally known as his "state of the world" message.
In it, he urged world leaders to meet the challenges of promoting peace, defending life and feeding a scandalously hungry world. Issues of sexual morality are rarely included in the Pope's address to diplomats so their inclusion this year underscored his concern about moves to legalise gay marriages.
"Today the family is often threatened by social and cultural pressures which tend to undermine its stability; but in some countries the family is also threatened by legislation which - at times directly - challenge its natural structure, which is and must necessarily be that of a union between a man and a woman founded on marriage," he said.
Calling the traditional family "the very sanctuary of life," the Pope said it was "a fundamental and irreplaceable condition" for raising children, for the well-being of society, and even for "the material prosperity of the nation".
Due to its role, the family "must never be undermined by laws based on a narrow and unnatural vision of man," he said.
Belgium and The Netherlands have legalised gay marriages, and Spain and Canada are considering it.
More than 4,000 gays were married in San Francisco last year but the marriages were later annulled by the State Supreme Court. US President George W. Bush has called on Congress to back a constitutional amendment to ban gay marriages.