By Europe correspondent Barbara Miller, wires
Photo: Mr Berlusconi has faced a string of legal troubles in recent times. (AFP Photo: Tiziana Fabi)
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Former Italian prime minister Silvio Berlusconi has been ordered to stand trial on corruption charges for allegedly bribing a senator.
Prosecutors in Naples allege the embattled tycoon paid senator Sergio De Gregorio more than $4.2 million to switch allegiances to his People of Freedom Party.
The move helped destabilise the government of then-prime minister Romano Prodi, which eventually collapsed.
Berlusconi was returned to power in 2008 elections that followed.
The development is the latest embarrassment for Berlusconi, who is appealing against several other convictions, including for having sex with an underage prostitute.
He is also facing expulsion from parliament over a tax fraud conviction which has been upheld.
Senator admits to being bribed
The senator himself helped investigators and was granted a 20-month sentence under a plea bargain by the hearing in Naples.
"I now believe I behaved in an absolutely reprehensible way and was aiming to bring down the Prodi government as part of a sort of holy war being waged by Berlusconi," Mr De Gregorio said.
"I have said sorry like no one does in Italy."
Mr Berlusconi's trial in Naples is due to start on February 11, 2014.
"I urge Silvio Berlusconi to leave the political scene, which would free Italy from a lot of dirt," Mr De Gregorio said.
The former prime minister was formally charged along with his former associate, Valter Lavitola, who is accused of acting as an intermediary in the bribe, lawyers said.
Mr Lavitola told the hearing that even if he had handled the money as alleged "there is no proof that I could have known that it was money for a bribe, I would have been simply a conduit".
But Mr De Gregorio says Mr Lavitola acted as the intermediary in the bribe.
Mr Lavitola was first placed under investigation in 2011 and fled the country for South America.
He returned after eight months on the run in April 2012 and was arrested at the airport.
'The encirclement of Berlusconi is continuing'
Supporters of 77-year-old Berlusconi immediately rallied around the three-time former prime minister, accusing prosecutors of bias.
"I can't believe it," said Daniele Capezzone, a lawmaker from Berlusconi's People of Freedom party.
"I think Italians fully understand that what has been happening in the past few years is an attack against a political leader who was freely and democratically chosen by millions," he said.
Another ally, senator Renato Schifani, said: "The encirclement of Berlusconi is continuing with a few extra knocks. The aim will not be achieved."
Berlusconi has often been accused by opponents of buying votes, but this is the first time he has officially been charged of corrupting a politician.
ABC/Reuters
