Former Italian prime minister Silvio Berlusconi was sentenced to four years in jail yesterday for tax fraud in connection with the purchase of broadcasting rights by his Mediaset television company.

The 76-year-old billionaire media magnate, who was convicted three times during the 1990s in the first degree before being cleared by higher courts, has the right to appeal the ruling two more times before the sentence becomes definitive.

That process is likely to be lengthy and he will not be jailed unless he loses the final appeal. Even then, because the crime was committed when an amnesty to prevent prison overcrowding was in place, the maximum possible jail time would be one year.

The ruling comes two days after Berlusconi confirmed he would not run in next year’s elections as the leader of his People of Freedom (PDL) party, ending almost 19 years as the dominant politician of the centre-right.

Milan judge Edoardo d’Avossa told a packed court that between 2000 and 2003, there had been “a very significant amount of tax evasion” and “an incredible mechanism of fraud” in place around the buying and selling of broadcast rights.

The court’s written ruling said Berlusconi showed a “natural capacity for crime”.

During a phone call to an evening news broadcast on one of his own channels, Berlusconi said there was no link between his decision to pull out of politics and yesterday’s ruling, and slammed the court for being politically motivated.

He called the verdict “political and intolerable” and said it showed Italy had become uncivilised, barbaric and was no longer a democracy.

Berlusconi lawyers Piero Longo and Niccolo Ghedini said the ruling was “totally divorced from all judicial logic”, adding that they hoped the “atmo-sphere” at the appeals courts would be different.

Berlusconi, one of Italy’s richest men, became prime minister for a second time in 2001 after winning a landslide election victory. Even while he was prime minister, he remained in effective charge of Mediaset even though he had handed over control of day-to-day operations, the court said.

The court also ordered damages provisionally set at €10 million to be paid by Berlusconi and his co-defendants to tax authorities.

The flamboyant Berlusconi, who is still on trial in a separate prostitution case, resigned as prime minister a year ago, handing the reins of government to economics professor Mario Monti.