Romanian senators have overwhelmingly voted for a measure that could be used to change the country’s constitution so that it defines marriage as a union between a man and a woman.

Romania’s constitution currently defines marriage as a union between “spouses” and the latest vote could be the first step to limiting the definition of marriage in the country.

If the definition is changed it would be very difficult for same-sex marriage to then be legalised.

Senators voted 107-13, with seven abstentions, to allow the referendum to go ahead.

The chairman of Romania’s ruling Social Democratic party indicated the referendum will be held in October.

The action follows the launch of a petition which was signed by three million Romanians last year, which demanded that the definition of marriage be changed.

“We’ve been a Christian nation for 2,000 years,” said Serban Nicolae, a senator for the Social Democrats.

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Opposition to same-sex relationships can be fierce in Romania, where attitudes are conservative and where homosexuality was only decriminalised in 2002.

The country, along with Poland, Slovakia, Bulgaria, Lithuania and Latvia, offers no legal protection to same-sex couples and does not recognise same-sex marriage.

The latest vote was condemned by Accept, a group that fights for equal rights for Romania’s same-sex couples.

The group accused the senators of “raising homophobia to state value and sacrificing constitutional protection for many families.”

Despite the vote Romania does have to recognise the residency rights of same-sex spouses after a landmark decision earlier this summer from the European Court of Justice.