The move by the Administration of the Patrimony of the Holy See is most likely the first outside audit of the Vatican's coffers. In addition to the audit, the Vatican also announced that it would create a supervisory board, overseeing the unit’s consultors.

The APSA office oversees the Vatican's property, provides cash flow to its bureaucracy, and manages the city-state's overall financial portfolio.

The review, headed by the global consulting firm Promontory Financial Group, will "allow for greater depth and detail in the verification of the financial condition and management" of the office, said the office's president, Cardinal Domenico Calcagno in a statement this week.

The statement did not disclose whether the review will be made public.

The review follows the questioning of former accountant, Msgr Nunzio Scarano, over his alleged involvement in a cash smuggling scheme on behalf of a family of shipping magnates. Scarano, who had worked for the office for 22 years, was arrested in June.

According to Italian media reports, Scarano has claimed that APSA conducted a series of financial improprieties, including illicitly allowing those outside the Vatican to participate in its funds and accepts gifts from banks in exchange for making deposits. Scarano is also accused of money laundering using the Institute for the Works of Religion, commonly called the Vatican bank.

In a bid to clear itself of previous allegations of its own impropriety, the bank openly published a yearly financial report for the first time on 1 October 2013, following Pope Francis’ orders for a review of the bank's operations to be conducted this year.