Pope Francis accepts the sudden resignation of a senior Vatican cardinal who will no longer be entitled to vote in conclave.

Cardinal Angelo Becciu, one of the Vatican's highest-ranking cardinals, resigned unexpectedly last night from his position as head of the Holy See's saint-making department after becoming embroiled in a real estate scandal.

Significantly, in addition to giving up his position as Prefect of the Congregation for the Causes of Saints, the 72-year-old Becciu renounces his rights as a cardinal.

This means that he will no longer be entitled to take part in a conclave to elect a new pope, after the current pontiff dies or resigns - a key privilege afforded to cardinals under the age of 80.

The Vatican took the highly unusual step of announcing Becciu's unexpected resignation late in the evening, on 24 September, in a one-line statement that gave no explanation for his sudden departure.

Cardinal Becciu becomes the first prefect of a Vatican department in modern times to renounce his cardinalatial privileges, reports The Tablet, indicating that the reason for Becciu’s resignation is particularly serious.

The Sardinian-born prelate was until 2018 deputy secretary of state, one of the most senior positions in the Holy See, responsible for large parts of the Vatican administration.

During his tenure in that office the Vatican became embroiled in a controversial deal in which the Secretariat of State used church money to purchase a luxury building on Sloane Avenue in London as an investment, reports The Guardian.

The Vatican is currently carrying out an investigation into this transaction - which Becciu has always defended - however Pope Francis is determined to root out any financial irregularities as part of ongoing reforms at the sovereign city-state.

So far the investigation has led to the suspension of five Vatican employees, the resignation of the Vatican's police chief and the departure of the former head of the Vatican's Financial Information Authority.

When contacted last night by Italian news agency Adnkronos for comment immediately after his shock resignation, Becciu replied simply: “I prefer silence.”

The last time a cardinal lost his "rights and privileges" was in 2018 when the Vatican ordered the "removal from ministry" of American Theodore McCarrick amid a sexual abuse investigation. Pope Francis subsequently laicised, or defrocked, McCarrick who was found to have sexually abused minors and seminarians.

In 2013 Cardinal Keith O’Brien of Scotland renounced his rights and privileges as cardinal, including the entitlement to vote in a papal conclave, after resigning over a sex scandal.