The Vatican is making it tougher to become a saint.

New procedures announced Monday call for more "rigor" and "sobriety" by bishops deciding to begin the process of beatification and determining the required miracles.

Cardinal Jose Saraiva Martins, head of the Vatican's sainthood office, recently suggested that the Vatican was overwhelmed by causes following the pontificate of the late Pope John Paul II, who elevated more people to sainthood than all his predecessors combined.

Saraiva Martins said there are more than 2,200 beatification and sainthood causes pending.

The cardinal, speaking at a news conference, stressed the need for a "true reputation for holiness" among candidates before a process begins. He said "rigorous historical research is obviously intrinsic" to the investigation.

During his 27-year pontificate, John Paul beatified 1,338 people and canonized 482 — more than all his predecessors combined since current procedures were introduced in the 16th century.

Asked about prominent cases now pending, the cardinal said the beatification cause of Archbishop Oscar Romero, the outspoken Salvadoran church leader who was killed in 1980 as he celebrated Mass, remains at a standstill while officials study whether his death made him a martyr for the faith.

To put Romero on the path to sainthood, the church must first determine if the archbishop of San Salvador was killed for religious reasons or for other motives, the cardinal said.

He also denied reports that the case of Pope Pius XII had been halted, saying he expected further research in the Vatican archives that "can't but help the cause" of the World War II pope.

Pius has been criticized by some Jewish groups and others who claim he did not speak up enough against the Holocaust. Saraiva Martins reiterated the Vatican stance that Pius "acted prudently" to avoid causing further suffering.