ROME (AFP) - A Tuscan court acquitted former Italian prime minister Silvio Berlusconi Thursday (Oct 21) of bribing a witness in the notorious "Rubygate" scandal about alleged sex fests he hosted.

The leader of the centre-right Forza Italia party had stood accused of paying a piano player present at his "Bunga Bunga" parties to lie about the evenings.

Girls who attended would later describe the events as sex fests, but Berlusconi has always insisted they were nothing more than elegant dinner parties.

"He is obviously relieved and satisfied," Berlusconi's lawyer Federico Cecconi was quoted by Italian media as saying, after the Siena court found the 85-year old and pianist Danilo Mariani innocent.

The defence had insisted money paid to Mariani was simply his performance fees.

The trial was part of the "Ruby-ter" investigation, the third involving his parties and alleged underage prostitute Karima El-Mahroug, aka "Ruby the heart-stealer".

The original trial, nicknamed "Rubygate" after El-Mahroug's nom de plume, saw Berlusconi beat an original seven-year prison sentence on appeal in 2014, a ruling upheld in Italy's highest court in 2015.

A second trial, named "Ruby-bis", concerned two of Berlusconi's close allies - former showgirl and Lombardy counciller Nicole Minetti and journalist Emilio Fede - who allegedly supplied young prostitutes.

Fede was sentenced to four years and seven months in prison and Minetti two years and 10 months.

The Ruby-ter trials deal with alleged payments made by Berlusconi to people who attended the parties in exchange for their silence.

Prosecutors have alleged that Berlusconi spent €10 million between 2011 and 2015, of which €7 million went solely to El-Mahroug in the form of cash, gifts, cars, provision of housing, payment of bills and medical expenses.

Under Italian law, local courts take charge of investigations of bribes paid within the city boundaries, and as payments were made in various cities, the case is being handled in different courts, including Rome and Milan.