A Vatican IT expert went on trial yesterday for allegedly helping Pope's Benedict XVI's former butler to steal confidential papal documents and leak them to the press.

Claudio Sciarpelletti, 48, pleaded not guilty to a charge of aiding and abetting Paolo Gabriele, the Pope's former personal assistant, who was sentenced last month to 18 months in jail for aggravated theft.

Sciarpelletti's lawyer, Gianluca Benedetti, claimed that an anonymous tip-off told Vatican police that the IT expert was a "close friend" of Gabriele.

A search of Sciarpelletti's desk in his Vatican office uncovered an envelope containing confidential documents addressed to the butler. Prosecutors accused Sciarpelletti of giving contradictory statements on the envelope's origin.

If found guilty, Sciarpelletti faces a possible sentence of up to one year in prison.