VATICAN CITY (Reuters) - The Vatican's second-highest ranking doctrinal official on Monday forcefully branded homosexual marriage an evil and denounced abortion and euthanasia as forms of "terrorism with a human face".

The attack by Archbishop Angelo Amato, secretary of the Congregation for the Doctrine of the Faith, was the latest in a string of speeches made by either Pope Benedict or other Vatican officials as Italy considers giving more rights to gays.

In an address to chaplains, Amato said newspapers and television bulletins often seemed like "a perverse film about evil". He denounced "evils that remain almost invisible" because the media presented them as "expression of human progress".

He listed these as abortion clinics, which he called "slaughterhouses of human beings", euthanasia, and "parliaments of so-called civilized nations where laws contrary to the nature of the human being are being promulgated, such as the approval of marriage between people of the same sex ..."

Amato spoke at a time when the Vatican and Italy's powerful Roman Catholic Church are at loggerheads over plans for a highly controversial law that would give unmarried heterosexual and homosexual couples some form of legal recognition.

The Church and Catholic politicians, even some in Prime Minister Romano Prodi's centre-left coalition, see the proposed law as a Trojan Horse and say it could lead to gay marriages.

Amato, who is said to be very close to Pope Benedict, criticized the media's coverage of ethical issues.