The fragile unity of Italian Prime Minister Romano Prodi’s government will be severely tested when proposals to offer legal recognition for same-sex unions are to be unveiled in the next few days.

Some are already seeing this as a referendum on Mr Prodi’s vulnerable nine-party centre-left coalition.

The situation has been made worse by intense lobbying from opposition MPs and the Catholic Church, with Pope Benedict XVI chastising the proposals as “anti-church and anti-family.”

Opinion polls show 69% of the country’s Catholics oppose the new laws, which would grant cohabiting couples some similar rights to married ones.

Despite the announcement by Silvio Berlusconi, leader of the largest opposition party, Forza Italia, said his MPs could have a free vote on the issue, political commentators suggest the result could be too close to call.

Mr Berlusconi’s position has already been criticised by some of his allies.

Fellow MP and former Senate leader Marcello Pera described the idea of giving opposition MPs a ‘conscience vote’ as “unbelievable.”

Similarly, a member of the centre-leaning National Alliance said his party was: “completely opposed to any debate which questions the nature of the sacrament of marriage.”

It has also emerged that the same party’s leader Gianfranco Fini had initially backed Prodi’s plans, but switched sides recently.

Viewed as a member of the “teodem” bloc of politicians who are sympathetic to the Catholic Church, Fini said:

“If the government wishes to pass a law on homosexual civil unions, it must demonstrate that it has a majority.”

Another opponent to the government’s proposals, the deputy Prime Minister Francesco Rutelli, had earlier this month cancelled a meeting with the Pope.

The government’s minister for family life met with a prominent cardinal over the weekend though the issue over same-sex unions was not thought to have been discussed.

The number of non-formalised same-sex unions in Italy doubled between 1994 and 2003, from 227,000 to 557,000.

Against this backdrop of political in-fighting came news that the Italian town of Bolzano had this week registered a homosexual civil union between two middle-aged men.

This was the first of its kind in the town whose local government had passed an ordinance which acknowledges same-sex civil unions back in 2003. Until now, the local ordinance had been largely symbolic.