The Senate moved to give the go-ahead to a controversial immunity bill for Berlusconi and three other top Italian institutional leaders, which will have the effect of freezing several criminal trials in which Berlusconi is involved, the Italian news agency ANSA reported.

The vote incensed opposition politicians, who said the measure raises Italy's premier, president and two Parliamentary speakers above the law.

"Dialogue with a government that wants to create a sovereign without limits is extremely difficult," opposition Democratic Party Senate whip Anna Finocchiaro told ANSA. "In a climate like this it's very hard to find a common thread of reason."

While the government said the move only brings Italy into line with other European nations, others to immediately begin a petition drive needed to repeal the measure.