A two-and-a-half year corruption trial that exposed infighting and intrigue in the highest echelons of the Vatican closes on Saturday with the key defendant, an Italian cardinal, hoping the court will accept his plea of innocence.

Cardinal Angelo Becciu, 75, a one-time Vatican power broker, is charged with embezzlement, abuse of office and trying to induce a witness to give false testimony.

Becciu, the most senior Vatican official ever to be charged with financial crimes, has denied all wrongdoing, as have the other nine defendants.

The panel of three lay judges of the Vatican's criminal court retired at 11:30 a.m. Rome time to consider its verdicts and was expected to announce them on Saturday afternoon.

Court President Giuseppe Pignatone, reading a note of thanks to lawyers and the media, acknowledged that the trial had been "particularly complex".

The trial, played out in 85 hearings, revolved mostly around a messy purchase of a building in London by the Secretariat of State, the Vatican's key administrative and diplomatic department.

Becciu held the number two position there in 2014 when it began investing in a fund managed by Italian financier Raffaele Mincione, securing about 45% of the building at 60 Sloane Avenue, in an upmarket district of the capital.

In 2018, by which time Becciu had moved to another Vatican job, the Secretariat of State felt it was being deceived by Mincione and turned to another financier, Gianluigi Torzi, for help in squeezing Mincione out and buying the rest of the building.

Torzi also fleeced the Vatican, according to prosecutors who have charged both men with fraud, corruption and embezzlement.

Under a cloud of embarrassment, the Vatican sold the building last year, taking an estimated loss of about 140 million euros ($150 million).

Becciu, who was fired by Pope Francis from his second job in 2020 for alleged nepotism but who remains a cardinal, has also been accused on charges related to tangential parts of the investigation.

The cardinal is accused of funnelling money and contracts to companies or charitable organisations controlled by his brothers on their native island of Sardinia.

Another accusation involves his hiring of Cecilia Marogna, a self-styled security analyst, also from Sardinia, as part of a secret project to help win freedom for a nun who had been kidnapped in Mali.

Marogna, 46, received 575,000 euros from the Secretariat of State in 2018-2019. The money was sent to a company she had set up in Slovenia and she received some in cash, prosecutors told the court.

Italian police said Marogna had spent much of the money for personal use, including luxury brand clothing and visits to health spas. She is charged with embezzlement.

The other six defendants include the former president and director of the Vatican's Financial Intelligence unit, the cardinal's former secretary, Father Mauro Carlino, and three former Vatican employees.

Four companies associated with individual defendants, two in Switzerland, one in the United States and one in Slovenia, were also indicted. The companies denied any wrongdoing.