Silvio Berlusconi
Italy's former PM Silvio Berlusconi has been expelled from parliament (Reuters)

The Italian senate has voted to expel Silvio Berlusconi from Parliament following his tax fraud conviction.

A majority of senators rejected all motions presented by Berlusconi's supporters to challenge a Senate committee's ruling saying that the former prime minister had to lose his seat over the conviction.

Ahead of the vote in the Senate, Berlusconi's supporters staged a demonstration outside the media tycoon's roman residence, the Grazioli Palace.

"It's a bitter day of mourning for democracy," Berlusconi said addressing the crowd of about 1,000 people.

"For us he will always be there," said Marilda Antonello, a supporter who held a banner reading "The law is not equal for everyone. Sick justice."

"He is our only leader. He is the only man who can take Italy forward," Antonello continued.

Inside the parliament, many senators for Berlusconi's party wore black clothing as a statement of grief over the expected expulsion.

The vote was based on a 2012 anti-corruption law stipulating that anyone sentenced to more than two years in prison cannot hold or run for office.

Berlusconi has long claimed the law shouldn't apply to him because his alleged offence was committed before the regulation was approved.

The vote came after Berlusconi's party - the People of Freedom Party - split in two after the 77-year-old threatened to pull support for the coalition government, which it was part of, if he was voted out.

Berlusconi and a group of his hard-line MPs re-launched the media tycoon's first political venture Forza Italia (Go Italy) and quit the government coalition with the centre-left Democratic Party.

Another faction led by Berlusconi's former protégée Angelino Alfano went on to form a new movement - the New Centre-Right - which has pledged to keep supporting Prime Minister Enrico Letta.

Conviction

Italy's Supreme Court upheld a tax-fraud conviction against Berlusconi in August.

The three-time prime minister was sentenced to four years in jail over alleged tax evasion worth several million euros by his media company Mediaset.

The prison term was reduced automatically to one year under a general amnesty, and Berlusconi will have to serve the remaining 12 months either under house arrest or through public service.