The Italian parliament has cleared the way to approving same-sex civil unions and granting some rights to unmarried heterosexual couples in a confidence vote called by Prime Minister Matteo Renzi to force the bill into law.
Italy had been the last major Western country not to legally recognise gay couples and an original draft law had to be heavily diluted due to divisions in Renzi's ruling majority.
The 41-year-old premier promised to prioritise legislation for gay rights when he took office in early 2014, but the bill proved to be one of the most contested of any of a raft of initiatives he has pushed.
It was the second confidence vote on the bill, which was originally presented in 2013. Such votes, called to curtail debate, force the government to resign if they lose. But Renzi's healthy majority in the lower house made this unlikely.
The Chamber of Deputies voted in favour by 369 votes to 193. The measure was due to be passed into law later on Wednesday by a final vote, which is a parliamentary formality.
The bill's long slog through parliament was accompanied by fierce debate and mass protests by Catholic groups saying it went too far and gay activists saying it did not go far enough.
The original bill had included the right for couples to adopt each other's children and referred to a duty of fidelity, stirring concerns that it was too close to traditional marriage.
The final version gives gay couples the right to share a surname, draw on their partner's pension when they die, and inherit each other's assets in the same way as married people.
Unmarried heterosexual couples get the right to be treated as each other's next of kin if one partner is taken ill, dies, or is imprisoned. They also get some rights to a shared home.
"We are putting this to a confidence vote because it wasn't possible to wait any longer after years of failed attempts," Renzi wrote on Facebook on Wednesday.
The so-called stepchild adoption clause was arguably the most disputed aspect of the bill. It stoked outrage among social conservatives and Catholics who saw it as a step towards legalising surrogate motherhood, which is illegal in Italy.
The new legislation specifically allows courts to keep granting homosexuals parental rights regarding each other's children in certain circumstances, a practice which has led to a handful of recent rulings in favour of homosexual parents.