Italy's Supreme Court has upheld a tax-fraud conviction against former Prime Minister Silvio Berlusconi, making a four-year prison sentence definitive.

The court has also ordered a review into his five-year ban from public office over following his fraud conviction last October.

However, three years of his sentence are not effective because of a 2006 amnesty. The remaining one year is likely to be served under house arrest or community service.

In Italy, it is unusual for defendants to serve sentences of just one year for a first offence, particularly at Berlusconi's age. He is 76 years old.

The five-judge panel began its deliberation following two days of arguments by prosecutors and Berlusconi's defense.

It is the first time Berlusconi has received a definitive conviction after previously been found guilty in several other criminal cases.

The case revolves around alleged fiscal irregularities worth several million euros in the tax affairs of Berlusconi's media company Mediaset in the 1990s and early 2000s.

Berlusconi, 76, and three others were convicted in October of tax fraud in the purchase of TV rights for Berlusconi's Mediaset network. Berlusconi was sentenced to four years in prison with a five-year ban on public office, which was confirmed on appeal earlier this year.

The state prosecutor has also recommended lowering Berlusconi's political ban from five years to three months citing discrepancies in the sentencing law.

Defence attorney Franco Coppi said the recommendation revealed a "blatant error" in the sentencing.

During his original trial, the prosecution claimed that from the 1990s to 2003, Mediaset bought rights for TV shows from American companies, such as Paramount, at artificially inflated prices for a total of €470m (£400m)

Berlusconi kept the surplus in slush funds in Swiss banks. The unlawful transactions passed through offshore bank accounts held by Agarma, an Egyptian national.

US companies were said to be unaware of what Berlusconi was doing.

He was also convicted in June of paying for sex with an under-age teen and then forcing public officials to cover it up in the high profile "Bunga Bunga" case. The court sentenced him to seven years in jail and a lifetime ban on public office.