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HELSINKI, Feb 17 (Reuters) - Finland's parliament voted down on Friday a citizens' petition demanding the repeal of a law that will allow same-sex marriages, securing the future of the law that will come into force next month.
In the vote, 120 members of parliament were opposed to the petition, while 48 supported it.
"That's it! The parliament confirms same-sex marriage to be 100 percent certain from here to eternity. Happy weddings," Green Party leader Ville Niinisto wrote on Twitter after the vote.
The law, passed in 2014 by the previous parliament, will end the distinction between same-sex unions and heterosexual marriages, giving same-sex couples equal rights to adopt children and share a surname.
Finland has been the only country in the Nordic region not yet to recognise same-sex marriage, although gay couples have been able to enter into registered partnerships since 2002.
Organisers of the "Genuine Marriage" petition collected more than 100,000 signatures demanding a repeal by arguing that a child was entitled to have both a mother and a father. In a surprise move, a parliamentary committee scheduled a vote.
Many lawmakers were opposed in principle to revising recent decisions, and only majority of MP's in the co-ruling Finns party, as well as in the opposition party Christian Democrats, voted in favor of the petition.
Bills on same-sex marriage had been blocked three times since 2006 until a petition brought about the 2014 bill, which passed by 101 votes to 90.
(Reporting by Jussi Rosendahl and Tuomas Forsell; Editing by Tom Heneghan)