Worldwide donations to the Catholic Church have plunged in the wake of sex abuse scandals that have eroded faith in the Vatican, a new book claims.

The Church’s finances are in such a dire state – a result of a toxic mix of incompetence, internal wrangling and corruption – that the Vatican risks a default by 2023, according to the expose.

The amount of money donated by ordinary Catholics to the Church, known as Peter’s Pence, has plummeted from €101 million in 2006 to €70 million in 2016 and may now be less than €60 million.

Only a fifth of the total goes to helping the poor and needy, with the rest held in bank accounts or used to plug gaps in the finances of the Curia, the Vatican’s governing body.

The revelations are based on scrutiny of 3,000 confidential documents obtained by an Italian investigative journalist, Gianluigi Nuzzi.

In his book, Universal Judgment, which was published on Monday, he portrays the Vatican as a viper’s nest of jealous cardinals, warring departments and avaricious officials who are adept at parallel book-keeping.

“If the pontificate of Frances fails, it won’t be because of the attacks of conservative Catholics or the crisis in vocations or because of the declining number of faithful,” Mr Nuzzi writes. “It will be because of the financial collapse that is coming ever closer.”