By Catherine Hornby
ROME (Reuters) - The head of the party that leads Italy's government called on Wednesday for Silvio Berlusconi to resign from politics after he lost his appeal against a tax fraud conviction, worsening tensions in the fragile left-right coalition.
Center-left Prime Minister Enrico Letta has reacted with restraint, desperate to avoid a government crisis, but the secretary general of his Democratic Party (PD) said all citizens are equal before the law and so Berlusconi should step down.
"It is the right thing to do and is what happens normally," Guglielmo Epifani told the Corriere della Sera. "What would have happened in the United States? In democratic countries, social and fiscal crimes are taken extremely seriously."
Berlusconi - head of the People of Freedom (PDL) party that shares power with the PD - is still a senator, despite the supreme court last week confirming a four-year jail sentence - commuted to one year - for tax fraud.
Like Letta, Berlusconi has sought to ease political tensions by saying it was important the government survive to help Italy get out of its worst recession since World War Two.
But Epifani, a member of the lower house, said Berlusconi, 76, should step aside regardless of the potential repercussions - which would likely include the PDL quitting the government.
"The principle of legality in a democratic state comes before any political consideration," he said.
The PDL, some of whose members are already urging Berlusconi to bring down the government and force an election as early as October, accused Epifani of dangerous provocation.
"Epifani is an irresponsible provocateur who is looking for a government crisis without being willing to take responsibility for it," said Luca D'Alessandro, a PDL spokesman.
Berlusconi is expected to serve his sentence either under house arrest in one of his luxurious residences or doing community service. Offenders over 70 years old are not normally sent to jail.
A Senate committee will begin debate on Wednesday evening on whether to eject Berlusconi from parliament. The PD is expected to back expulsion but the decision is unlikely to come before next month before going to the full Senate for the final vote.
Voting on the expulsion is the most likely spark for a crisis in the three-month-old government, although President Giorgio Napolitano, like Letta, is against early elections, which he says Italy cannot afford during an economic emergency.
PDL members have attempted to lobby Napolitano for some way of keeping Berlusconi in politics, saying he is the irreplaceable leader of 10 million Italians who voted for him in elections last February.
A pardon is considered impossible for a string of legal and institutional reasons and Napolitano has expressed irritation at media speculation on his likely options.
Berlusconi's conviction last Thursday for the fraudulent purchase of broadcasting rights by his Mediaset media empire was the first definitive ruling against him in dozens of trials since he stormed into politics in 1994.
The media mogul accuses leftist magistrates of trying to subvert democracy by forcing him out of politics.
(Editing by Barry Moody and Robin Pomeroy)