ROME, Apr 15 (Reuters) The dispute over who won Italy's general election took a new twist today when an ally of Prime Minister Silvio Berlusconi said he had found a mistake in the tally that would reverse the ruling coalition's defeat.
The centre-left opposition alliance, which claimed victory four days ago in the April 9-10 vote, dismissed the assertion by Roberto Calderoli, a former reforms minister.
Its leader, Romano Prodi, said Berlusconi should apologise to the nation and finally admit he lost the closest election in modern Italian history, whose outcome awaits a court ruling.
Berlusconi's best hope of overturning Prodi's 25,224-vote advantage in the lower house of parliament appeared to have vanished yesterday when the interior ministry said there were not enough disputed ballots to change the election outcome.
The prime minister, who is also Italy's richest man, has alleged widespread irregularities.
Calderoli, a member of the Northern League party, reignited debate today by saying he had discovered a batch of 45,580 votes he said were picked up illegally by a centre-left political party, the Lega Alleanza Lombarda.
''If somebody is thinking about heading down to the square to celebrate with this vote tally the way it is, that would be like a coup,'' said Calderoli, adding he made a formal complaint to election authorities.
He said Lega Alleanza Lombarda had registered its list of candidates in only one district, not enough, he said, for its votes to count under Italy's new electoral law.
DELIRIOUS? ''We invite Calderoli to reread the law that he says he wrote,'' Prodi's coalition responded in a statement. ''At no point in the electoral law is it written, in fact, that there is a minimum number of districts'' where parties need to register.
In an earlier statement, Prodi said: ''Berlusconi should acknowledge how things have turned out and I think after everything he said about vote-rigging, he should say he's sorry.'' Most of Berlusconi's allies have already distanced themselves from the charges of widespread irregularities.
But Sandro Bondi, chief coordinator of Berlusconi's Forza Italia party, backed Calderoli.
''If this is confirmed, it is clear that the provisional electoral result that was announced needs to be completely overturned, because the (centre-right coalition) has a majority in the lower house of nearly 20,000 votes,'' Bondi was quoted as saying by Italian news agency ANSA.
Italy's election law guarantees a solid majority in the lower house of parliament to whoever wins the vote for it, no matter how small the margin of victory. In the Senate, which has a different system, Prodi has just a two-seat majority.
Berlusconi said in a television interview late yesterday that the centre-left ''have not won yet and I think that from a moral point of view we are the winners''.
The country is awaiting an official confirmation of the election results by Italy's highest court for legal appeals, to end the debate once and for all. That is not expected to come before next week at the earliest.
The centre-right has said Prodi, who headed a short-lived 1996 government, would be a lame-duck prime minister, unable to keep a grip on his Union alliance that bridges a vast ideological span, from communists to Roman Catholic centrists.
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