The two largest parties in Italy's ruling centre-left alliance prepared on Monday to launch a single force which Premier Romano Prodi hopes will lead the Left in the decade ahead.
The Democratic Party, whose creation Prodi has been urging for years, is expected to begin taking shape this week as the Democratic Left and the Daisy parties agree at respective congresses to merge.
"A great adventure which goes beyond political parties is now beginning," Prodi said on Monday, on the sidelines of a visit to Japan.
According to the hopes of its promoters, the Democratic Party (PD) will formally come into existence in the spring of 2008 and face its first major test at European elections the following year.
As well as agreeing to merge, the two party congresses being held this week are also expected to work out a sort of 'road map' which will enable a founding assembly to agree on a statute within a year.
The constituent members of that assembly are to be chosen according to procedures that still have to be decided. It is thought likely that they will be elected by centre-left voters through a poll next autumn.
Recent opinion polls suggested that the new PD would only garner about 23% in a national election. This is 5% less than the two component parties scored in 2006 elections for the Senate.
But Prodi has dismissed the result of the poll as meaningless. "Of course it doesn't inspire people. It hasn't been formed yet. They're still talking about how to do things, which is the toughest part," he said at the weekend.
The lead up to this week's crucial party congresses has been spoilt for Prodi by the refusal of the Italian Socialists to come on board and by the apparent possibility that part of the Democratic Left will also split away.
There has also been some unseemly polemics about who will lead the new party. Although Prodi himself has been the driving force, there have been suggestions that he should have this role and be premier.
The premier has refused to even discuss the leadership question, saying now is the time for "enthusiasm" and wide-ranging debate on ideas, not for this sort of detail.
In the meantime, he has denied anointing Rome Mayor Walter Veltroni as the person likely to eventually take the reins of the PD.
Democratic Left heavyweight Massimo D'Alema, former premier and current foreign minister, has said Prodi should lead the PD "for now", without indicating when a change should come.
Daisy leader Francesco Rutelli has said any discussion of the leadership is "premature and immature".
Italy's centre-right opposition is scornful of the plans for a broad centre-left party encompassing former Communists and Christian Democrats.
"It'll just be an anti-Berlusconi party," said centre-right christian democrat Gianfranco Rotondi.
