Vatican finances were one of the many Church and international topics the 85-year-old pontiff discussed in an exclusive interview with Reuters in his Vatican residence on July 2.
The interview took place a day after the Vatican announced it had completed the sale of the building on Sloane Avenue in Chelsea, taking an estimated hit of about 140 million euros ($A208 million).
Ten people including a Vatican cardinal and two Italian financial brokers are on trial in the Vatican on charges including embezzlement, fraud, money laundering and extortion relating to the building.
The Pope was asked if he believed enough controls were now in place so that similar scandals could not take place again.
"I believe so," he said.
The Vatican's Secretariat of State first invested in the building in 2014 with funds from its own sovereign wealth fund, managed without external controls.
It had resisted oversight even from the Secretariat for the Economy, which the Pope instituted in 2014 to oversee all Vatican finances and put a lid on decades of scandals caused by the fragmentation of finances, in which different departments exercised control in a fiefdom-like way.
As a result of the botched and embarrassing London deal, the Pope stripped the Secretariat of State of control over its own investment funds in 2020.
Last month, he instituted a committee to oversee the ethics of all Vatican investments.
"Before, the administration (of Vatican money) was very messy," the Pope said, adding that the Secretariat for the Economy is now staffed by expert, technical people "who don't fall into the hands of quote-unquote benefactors or friends, who can make you slip up."
He gave the example of priests who had no financial experience being asked to manage the finances of a department and who in good faith sought outside help from friends in the outside financial sector.
"But sometimes the friends were not The Blessed Imelda," he said, referring to a 14th century 11-year-old Italian girl who is a symbol of childhood purity.
"And so what happened, happened," the Pope said.
He blamed "the irresponsibility of the structure" for past financial scandals, saying the administration of money "was not mature".
In the interview, Francis praised Pell as "the genius" who had insisted that the Vatican needed an overarching economy ministry to control money flows and combat corruption.
Pell was the first head of the Secretariat for the Economy, receiving a mandate from the Pope to clean up the Vatican's murky finances.
Pell, now 81, left the post in 2018 to face sex abuse charges dating back decades in Australia.
He spent 13 months in solitary confinement before being cleared of all charges on appeal in 2020.
Cardinal Angelo Becciu, whom Pell has accused of having resisted financial reforms when he was number two at the Secretariat of State, is currently one of 10 defendants at the corruption trial over the London real estate deal.
All of the defendants have denied wrongdoing.
