ROME—An Italian cardinal whose former office has been embroiled in a financial scandal resigned suddenly Thursday from his Vatican post and renounced his rights as a cardinal, a surprise escalation of an affair that has overshadowed that Holy See for the last year.

The extraordinary move was announced without explanation in a terse evening communique from the Holy See press office.

Cardinal Giovanni Angelo Becciu had been head of the office that oversees the canonization of saints. At age 72, he would still have been eligible for the next eight years to vote in a conclave to elect a future pope. Some Vatican watchers even spoke of him as a serious candidate for the papacy.

But for the last year, he has been shadowed by association with scandal that has touched several of his former subordinates.

Last October, Vatican police raided the offices of the powerful Secretariat of State, where Cardinal Becciu had served as the second highest official until June 2018. The police, who also raided the offices of the Vatican’s financial watchdog, were investigating an investment in real estate in London’s posh Chelsea neighborhood.

The Vatican prosecutor’s investigation came in response to a complaint from the Vatican Bank, which had objected to a request from the Secretariat of State for a loan of more than €100 million, equivalent to about $116 million, to finance the purchase. The Vatican Bank viewed the deal, which required clearance by the financial watchdog, as suspicious.

Several Vatican employees have been investigated in connection with the deal but none has been charged with wrongdoing. In June, Vatican prosecutors charged an Italian businessman with counts of extortion, embezzlement, fraud and money laundering, carrying a potential sentence of up to 12 years in connection with the deal.

Cardinal Becciu hasn’t been accused of wrongdoing in the matter. He didn’t respond to a request for comment Thursday.

The Vatican communique referred to the cardinal as “His Eminence,” suggesting that he has retained his title.

It is extremely rare for a cardinal to be publicly disgraced in such a way. In 2018, then-Archbishop Theodore McCarrick, a former archbishop of Washington, resigned from the College of Cardinals after a church investigation found credible a charge that he had sexually abused a minor in the 1970s. The next year, after a Vatican trial found him guilty of sexual abuse and sexual misconduct with adults, he was removed from the priesthood, the first former cardinal in modern times to receive that punishment.

In 2015, Scottish Cardinal Keith O’Brien renounced the rights and privileges of cardinal—including the right to vote in a conclave—but retained his title after an investigation into allegations that he had sexually harassed adult seminarians in the 1980s. Cardinal O’Brien died in 2018.

Write to Francis X. Rocca at