A bill to give legal recognition and protection to same-sex couples was presented to parliament on Wednesday, a significant milestone on Italy's tortuous path to legalizing civil unions.

Italy is the only major country in the West that has not yet offered homosexual couples any legal rights as successive governments ran into determined opposition from parties close to the Roman Catholic Church.

Prime Minister Matteo Renzi had promised that a bill allowing civil unions would become law this year, but that looks highly unlikely, with his main coalition partner, a small center-right group, fiercely opposed to the project.

However, looking to speed up the process, the government on Wednesday briefly presented its bill to the upper house Senate, a move which could open the way for its approval in early 2016.

"We are finally here with a civil union bill that is very strong," said Senator Monica Cirinna, author of the text.

"It is not exactly equal to other marriages, which I would have preferred, but it is a bill that recognizes all social rights," she told Reuters.

While stopping short of sanctioning full gay marriages, the legislation offers some of the benefits enjoyed by married couples, such as a share of a deceased partner's pension and automatic inheritance.

The bill would also apply to unmarried heterosexual couples.

"GOD'S DREAM"

One major sticking point is that the draft law would allow a homosexual to adopt the child of their partner should that partner die. The coalition New Center-Right (NC) party says this will eventually pave the way to full adoption rights and has sought to block it in a parliamentary commission.

Breaking the logjam, Renoir's Democratic Party (PD) decided this week to halt discussion in the commission, bypass hundreds of amendments and bring the text to the full house.

From the end of this week, the Senate calendar will be dominated by discussions over the 2016 budget, but the civil rights law should be able to return to the chamber before the end of the year and then move to the lower house for debate.

A number of opposition parties, including former premier Silvio Berlusconi Forma Italia group, have said they support the plan, meaning it should pass relatively easily when it finally comes to a vote, despite Roman Catholic opposition.

The parliamentary move coincides with a meeting in the nearby Vatican of bishops called to discuss the role of the family. The Church has warned there will be protests if the law passes and Pope Francis said this month that marriage between a man and a woman was "God's dream for his beloved creation".

(Additional reporting by Antonio Denit; Writing by Crispian Balmer; editing by Ralph Boulton)