The Vatican is on the verge of bankruptcy, according to a recent book by an Italian investigative journalist.

La Repubblica, which published excerpts of the work, said the book "Giudizio Universal" was published Monday in Italy by Gianluigi Notici, who often publishes materials citing leaked documents.

The book says the Pope received an internal report in May 2018 indicating that "the deficit of the greatest ink has reached alarming levels and is prone to bankruptcy."

Expenditures by the Vatican central administration increased by 62 per cent, from 4.16 million euros ($ 3.18 million) in 2015 to 6.26 million euros in 2017, the book said.

On the other hand, donations to the Pence Boutros Fund, whose direct payments to the Pope, have fallen from 101 million euros in 2006 to 51 million euros in 2018, according to the book.

Noticii also reiterated allegations that the Vatican mismanages his important real estate assets and uses only 20% of Pence Peter's resources for charity.