Italian Prime Minister Enrico Letta is battling to salvage his coalition ahead of a confidence vote on Wednesday after five ministers handed in their resignations.
On Saturday Silvio Berlusconi withdrew his party’s support following the government’s decision to go ahead with a planned rise in VAT on 1 October.
Five ministers from Mr Berlusconi’s People of Freedom (PDL) party handed their “irrevocable resignations” to the government on Monday, Italian news agency ANSA reported.
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The ministers are Deputy Prime Minister and Minister of Interior Angelino Alfano, Minister of Agriculture Nunzia Di Girolamo, Minister of Health Beatrice Lorenzin, Minister of Infrastructure and Transport Maurizio Lupi and Minister of Constitutional Reforms Gaetano Quagliariello.
Mr Letta will go before parliament to seek support to continue in a confidence vote, leaving two days of manoeuvring among the parties, starting with a meeting between Mr Berlusconi and PDL parliamentarians.
Mr Letta enjoys a commanding majority in the lower house but would need to win over a couple of dozen senators from Mr Berlusconi’s PDL party or opposition parties including the anti-establishment Five Star movement to be able to be sure of parliamentary support.
The outcome of the vote is uncertain as some senators from Mr Berlusconi’s centre-right party have shown increasing unease over the shock decision to withdraw government support.
As many as 20 senators from the centre-right party of Mr Berlusconi are ready to form a breakaway group unless the former premier backs down on his hard line to bring down Italy’s government and head to elections, a top member of the party told Reuters.
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The threat, which MPs from the PDL are going to level at Mr Berlusconi during a meeting on Monday, may give the prime minister a chance to save his government despite the resignations.
However, Beppe Grillo, the figurehead of the Five Star Movement, said he was keen for new elections.
He wrote on his blog: “We need to go to the polls to win and save Italy. It’s the last train.”
Financial markets, which have been increasingly nervous about Italy after a week of rising political tensions, are expected to sell off government bonds and stocks, adding to the atmosphere of crisis.