The Vatican had vowed that it will never stop insisting that marriage can only be between a man and a woman.
Just days after three US states approved same-sex marriage by popular vote in the recent election, the Vatican has taken a stance against gay marriage with a "media blitz" that includes a front-page article in Saturday's Vatican newspaper L'Osservatore Romano.
There was also a Vatican Radio editorial in which the pope's spokesman asked why gay marriage supporters don't also push for legal recognition of polygamous marriages as well.
Along with the US, Spain has also upheld its gay marriage law and France is pushing ahead with legislation that could see same-sex marriage legalized as early as next year.
Catholic teaching holds that homosexuals should be treated with dignity but that homosexual acts are "intrinsically disordered."
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Rev. Federico Lombardi, the Vatican spokesman, said that homosexuals can have their rights protected by means other than through legal marriage.
He added that children should be able to say they have a father and a mother.
"If not, then why not contemplate freely chosen polygamy, and naturally so as to not discriminate, polyandry?" he asked.
Polyandry is when a woman has two or more husbands.
"As a result, don't expect the church to stop insisting that society recognises a specific place for marriage between a man and woman," he said.
The Church has also clashed with the Obama administration over the contraception mandate which exempts houses of worship but applies to faith-affiliated employers.
The US Conference of Catholic Bishops has said the mandate is a violation of religious freedom.