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By Alberto Sisto and Stephen Jewkes
ROME/MILAN, March 31 (Reuters) - The chief executive of Italy's biggest listed company Eni has been sentenced to prison, according to a court document seen by Reuters on Monday, putting a question mark over his chances of being reappointed head of the oil major.
A ruling by a court in the north-eastern town of Rovigo said Eni CEO Paolo Scaroni had been sentenced to three years in prison and had also been banned from holding public office for five years, without giving details on the case.
Sources close to the matter said the ruling regarded the violation of environmental norms at the Porto Tolle power plant in northern Italy in a period when Scaroni was CEO at Italy's No 1 utility Enel.
In a separate emailed statement, Scaroni said he was shocked by the decision.
"I am in no way involved in this matter and will appeal immediately," he said. "As shown by the defence, Enel's Porto Tolle station has always met the existing standards including at the time of the facts contested," he said.
The Italian court said in the document seen by Reuters that the CEO of utility Enel, Fulvio Conti, had been acquitted in the same case.
Scaroni has already served three terms as CEO at state-controlled Eni and his current mandate expires in May.
The Italian government wants state-controlled companies to eject from their boards any director charged of financial crimes, in a drive to fight corruption and improve corporate accountability. (Reporting by Alberto Sisto in Rome and Stephen Jewkes in Milan; Editing by Valentina Za and Pravin Char)