Couples of the same sex will also have the legal option to adopt children following the parliamentary vote on February 15, with 176 votes in favor and 76 against.

Prime Minister Kyriakos Mitsotakis stated that the new law will "courageously eliminate a serious injustice".

However, it has divided the country, with strong opposition led by the influential Orthodox Church. Supporters organized a protest rally in Athens.

Many displayed banners, carried crosses, recited prayers and chanted passages from the Bible in Syntagma Square in the capital.

The head of the Orthodox Church, Archbishop Ieronymos II, stated that the measure would "corrupt the social cohesion of the homeland".

The act needed a simple majority to pass the 300-seat Parliament.

Mitsotakis promoted the law but required the support of opposition parties to pass it, given that many members of his ruling center-right party opposed it.

"People who have been invisible will finally be seen around us, and with them, many children will finally find their rightful place", said the prime minister in Parliament during the pre-vote debate.

"The reform improves the lives of many of our fellow citizens without taking anything away from the majority's lives", he added.

The vote was welcomed by LGBTQ organizations in Greece.

"It's a historic moment", said Stella Belia, the head of same-sex parents' group Rainbow Families, to Reuters. "It's a day of joy", she said.

Fifteen out of the 27 European Union member states have already legalized same-sex marriage. This is permitted in 35 countries worldwide.

Until now, Greece had lagged behind some of its European neighbors, primarily due to the opposition of the Church.

Greece is the first country in southeastern Europe to achieve marriage equality.