Italian Prime Minister Silvio Berlusconi this evening denounced Italy's general election as fraudulent and said official results giving victory to his centre-left rival Romano Prodi had to be overturned.
Mr Berlusconi has refused to concede defeat in the April 9-10th vote, and demanded a review of thousands of disputed ballots.
"The election result has to change because there was widespread fraud," Mr Berlusconi told reporters after meeting President Carlo Azeglio Ciampi this evening.
"Did you think you were about to be free of me?" he said, adding that the voting irregularities had been at the expense of his centre-right alliance.
But Mr Prodi, attending a victory celebration in his home city of Bologna, in northern Italy, dismissed the allegation.
"We have won ... Berlusconi has to go," Mr Prodi said.
Berlusconi's accusations raised the prospect of a long, drawn out battle over the election result which could paralyse Italian politics.
The prime minister himself said there was no time limit for a review of the vote, adding that he thought it would take several days. "There are statements from 60,000 voting stations to be checked, one by one," he said.
According to data provided by the Interior Ministry, the centre-left won the vote for the lower house of parliament by a margin of just 25,000 votes out of 38.1 million cast.
The tight margin has left many Italians wondering how long the next government will last and financial markets fretting that Mr Prodi will not have a big enough majority to push through unpopular reforms needed to revive the flagging economy.
Prodi has said he can govern for a full five year term. Yesterday, Mr Berlusconi said some 40,000 disputed ballots had to be checked before either side could claim victory.
Such checks are routinely carried out by local authorities after an election and were expected to be completed by Friday.
Most commentators said the review was unlikely to alter the result and centre-right leaders kept a low profile today, some ministers appearing to have accepted Mr Prodi's win.
Possibly giving the centre-right fresh ammunition to question the results, police found boxes containing valid filled in ballot sheets near a rubbish bin in Rome.
Italy's electoral system, which gives a premium of extra seats to the winning coalition, means Mr Prodi's side has 348 seats in the lower house against 281 for Mr Berlusconi's bloc.
In the upper house, where seats are allocated differently, Mr Prodi's bloc has just 158 against 156 for the centre-right.