ROME (AFP) - Italian lawmakers on Monday began hearings to decide whether Silvio Berlusconi should be expelled from Parliament following his criminal conviction in an unprecedented case that has stoked political tensions.

Berlusconi's defiance over the possible sanction is unique in Europe's recent political history and threatens the coalition between his People of Freedom (PDL) and the centre-left Democratic Party (PD).

As the eurozone's third biggest economy struggles to exit a recession that has led to record unemployment, the 76-year-old former prime minister and billionaire tycoon has once again taken the political centre stage.

A Senate committee began its meeting to discuss his ejection, even though stalling tactics from Mr Berlusconi's supporters could drag the process on for months before a compulsory final Senate vote.

The meeting began with a lengthy statement in Berlusconi's defence by PDL senator Andrea Augello.

Berlusconi has complained that a new law against criminals in Parliament adopted last year with the aim of cleaning up Italian politics and approved with votes from his own party in fact violates his rights.

The three-time premier has appealed to the European Court of Human Rights in Strasbourg, arguing that the law should not apply for convictions relating to crimes committed before its adoption, as in his case.

The law would also prevent Berlusconi from taking part in the next general election set for 2018.

The PD's leadership has said it will vote to apply the law but the PDL argues that Berlusconi should receive "political freedom of movement" since he leads a party for which millions of Italians have voted.

Some of Berlusconi's critics have pleaded with him to resign voluntarily and spare Italy more embarrassment.

PD leader Guglielmo Epifani has warned that Italy risks looking like a "banana republic" internationally.

Nichi Vendola, leader of the leftist SEL party, said the case is "unique for a Western democracy".

Berlusconi could lead his party from outside Parliament but expulsion would be a blow as he has been a lawmaker ever since entering politics in 1994.

The stand-off follows a landmark supreme court ruling on August 1 that turned down Berlusconi's final appeal against a tax fraud conviction and upheld a 12-month sentence with a hearing next month to decide whether he should be committed to house arrest or community service.

An appeals court will also begin hearings on October 19 to decide whether Berlusconi should be temporarily banned from holding public office for one to three years.

The verdict was the first definitive ruling against him in decades of legal proceedings that Berlusconi says are part of a left-wing crusade by prosecutors.

He is also currently appealing convictions for having sex with an underage 17-year-old prostitute and abusing his official powers when he was prime minister.

Most experts agree that Berlusconi's supporters are unlikely to bring down the government, even though they have repeatedly threatened to do so if their leader is expelled from Parliament.

Prime Minister Enrico Letta warned on Sunday that political instability "carries a cost" but said he did not believe the PDL would abandon the coalition.