Mr Berlusconi insists he should not be 'distracted' from governing
Prime Minister Silvio Berlusconi says he feels "invigorated" after Italy's constitutional court overturned a law granting him immunity whilst in office.
"I will defend myself... and show what stuff I'm made of," Mr Berlusconi said.
The ruling means he could face trial in at least two court cases, including one accusing him of corruption.
But it does not mean Mr Berlusconi will be forced to resign, as long as he can keep together his conservative coalition, which dominates parliament.
His allies have stood firmly behind the 73-year-old billionaire prime minister.
Italy's opposition has called on Mr Berlusconi to step down, but his main coalition partner, the Northern League, has backed him.
The news has stunned Italy, where the prime minister's widespread public support has been damaged by a series of sex scandals and his wife's announcement that she is divorcing him.
While admitting he is "no saint", Mr Berlusconi denies having paid for sex or conducting improper relationships.
Wednesday's ruling means Mr Berlusconi could be called as a witness in an appeal starting on Friday by his one-time co-defendant David Mills, La Stampa newspaper reported.
The British tax lawyer - the estranged husband of UK minister Tessa Jowell - was convicted of accepting a $600,000 bribe to lie in court to protect Mr Berlusconi and sentenced in February to four-and-a-half years in prison for corruption.
Both men denied any wrongdoing.
The 15-judge Constitutional Court ruled on Wednesday that immunity legislation pushed through by Mr Berlusconi's administration in 2008 violated the principle that all citizens were equal in the eyes of the law.
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