ROME (Reuters) - Silvio Berlusconi's PDL party walked out of the Senate ahead of a confidence vote on economic measures on Thursday, ratcheting up tension with the Italian government of Prime Minister Mario Monti ahead of elections next year.
The symbolic move did not threaten the government's survival but showed strong disapproval of Monti's technocrat administration by the largest party backing him in parliament, following implicit criticism of People of Freedom (PDL) leader Berlusconi by Industry Minister Corrado Passera.
In an increasingly fevered pre-election atmosphere, Berlusconi dropped a strong hint late on Wednesday that he could go back on previous statements and run for a fifth term as prime minister in the election, expected in March.
In a television interview on Thursday, Passera expressed strong reservations about a return by Berlusconi.
"Anything which can make the rest of the world or our partners imagine that we are turning back is not a good thing for Italy," he told state broadcaster RAI.
PDL Senate leader Maurizio Gasparri said the party would not take part in the vote on Monti's latest package of reforms but would not vote against the decree or formally abstain, either of which would cause the government to fall.
While the PDL's action had no direct impact on either the government or the decree, it represented a significant increase in tension ahead of the election as Berlusconi fights to reverse a collapse in the party's popularity.
The centre-left Democratic Party (PD), which also backs the government, said that if Monti did not have the full support of one of the two main members of the cross-party alliance that supports him in parliament, then he should ask President Giorgio Napolitano to bring forward the elections.
PD Senate leader Anna Finnochiaro said that the PDL's refusal to take part in the vote suggested the government no longer had a majority.
"The political problem is hugely important. I think that Monti should go to see the President in line with the established practice," she told reporters.
The comment appeared a tactical move aimed at putting pressure on the PDL rather than a real push for Monti to dissolve parliament.
The confidence vote proceeded normally, without the PDL senators. The result was expected shortly.
(Reporting by Giuseppe Fonte, writing by James Mackenzie; editing by Barry Moody)