ROME (Reuters) - Italy's referendum on constitutional reform in December is widening splits in Prime Minister Matteo Renzi's Democratic Party (PD), with a vocal minority of its lawmakers refusing to join his campaign in favour of the changes.
On Thursday the level of personal acrimony intensified when Renzi's closest aide launched a bitter attack against former PD leader and ex-Prime Minister Massimo D'Alema, one of the most prominent opponents of the reform.
Renzi's undersecretary Luca Lotti said D'Alema's opposition to the plan to curb the powers of the Senate and centralise decision-making was motivated by "hatred" towards his leader for overlooking him for a top European Union job.
D'Alema had never forgiven Renzi for proposing Federica Mogherini for the post of EU representative for foreign affairs and security in 2014, Lotti said, calling the former premier "blinded by anger" and "consumed by resentment."
Renzi has staked everything on the Dec. 4 referendum, promising to resign and abandon politics if he loses. The majority of recent opinion polls suggest the reform will be rejected, though a large proportion of voters remain undecided.
The problem for Renzi is that D'Alema is not the only prominent PD figure hampering his campaign. Another former party leader, Pier Luigi Bersani, is among several PD politicians who say that, in conjunction with a new electoral law pushed through by Renzi, the reform will give too much power to the prime minister and make Italy less democratic.
With all the opposition parties lined up against the proposed changes, the fact that many in Renzi's own party are also not supporting him gives him an arduous task.
Renzi is accused by left-wing PD traditionalists of moving the party too far to the right, and even if he wins, the internal hostilities laid bare by the referendum campaign will not be easy to heal. Many commentators forecast that what has so far been a trickle of PD defections could intensify after the vote.
This week opposition parties launched a legal appeal to change the wording of the question on the ballot sheet, which cites the more popular aspects of the reform but none of the less popular ones. The Rome court said it would take a decision in a few days.
With less than two months to go, the 'Yes' camp, which is advised by U.S. presidential campaign consultant Jim Messina, has the advantage of greater financial resources and has launched a billboard campaign all over Italy.
On Wednesday one of its best known supporters, Oscar-winning comedian Roberto Benigni, caused a stir when he said on a popular television show that a win for 'No' would be "worse then Brexit", in reference to Britain's decision to leave the EU.
Editing by Mark Trevelyan