Italy minister says snap polls possible in autumn

* Early poll only option if govt falls-N. League's Maroni

* First test will be confidence vote on junior minister

By Silvia Aloisi

ROME, Aug 4 (Reuters) - Italy could hold snap elections in the autumn if Prime Minister Silvio Berlusconi's centre-right government falls, a minister from the Northern League said hours before a crucial vote in parliament.

Interior Minister Roberto Maroni said the two-year government was "sailing without compass" after last week's split between Berlusconi and his long-time ally Gianfranco Fini.

Fini, the lower house speaker and co-founder of Berlusconi's People of Freedom party (PDL), has set up a break-away faction in parliament that could deprive Berlusconi of his majority, raising the prospect of a government collapse.

Italian elections have traditionally been held in the spring or early summer but Maroni said there was nothing to stop the country voting at any time.

"If the ship hits the rocks, we go back to the polls," said Maroni, an influential member of the Northern League that is now Berlusconi's main coalition partner.

"I know there are no precedents of holding elections in the autumn, but they should not be ruled out in the face of a serious political crisis," he told Corriere della Sera daily.

He also repeated the Northern League's opposition to any possible move by President Giorgio Napolitano to try to identify a new parliamentary configuration as the basis for an interim government to manage business until elections due in 2013.

"He could look but he wouldn't find it because without the League there is no alternative in either the Lower House or the Senate and any interim government would only last a week, after which he would have to accept reality and dissolve parliament."

TEST OF STRENGTH

Berlusconi faces a test of strength on Wednesday when the lower house votes on a no-confidence motion against a junior minister under investigation in an influence-peddling scandal.

Fini's allies in the chamber, alongside three smaller centrist parties, have agreed to abstain in the vote, putting off a fullblown showdown but still scoring a political point.

Berlusconi is also said to favour early polls if he does not have enough backing in parliament, and will be closely watching Wednesday's vote -- whose result is expected around 1800 GMT -- to gauge how much he has been weakened by the split with Fini.

The traditional summer parliamentary break is expected to bring a truce until September but after that, the situation remains extremely unclear.

If a government resigns and Italy's president fails to find someone who can form another one, he can dissolve parliament and call early elections -- usually held about two months later.

Napolitano, a former communist whose relations with Berlusconi are patchy, has gone on holiday -- which commentators in Italy see as a sign that a government crisis is not imminent.

But few in Italy are betting that the current executive will last long. Berlusconi's popularity has been sliding in recent months, but the centre-left opposition is so fragmented that he could win an early election.

Maroni also quashed speculation that Economy Minister Giulio Tremonti, whose steady management of Italy's strained public finances has been credited with warding off a Greek-style crisis, could head an alternative government.

"I have spoken to him and he is in perfect agreement," Maroni said of Tremonti, who is considered close to the Northern League. "Proposing Tremonti is a gesture of desperation on the part of people looking for a way out who have nothing to offer."