A U.S.-based group that fights anti-Semitism urged Pope Benedict on Thursday to suspend the sainthood process for Pope Pius XII, whom critics accuse of turning a blind eye to the death of Jews during World War Two.

The Anti-Defamation League said the process should stop until secret World War Two Vatican archives are declassified and fully examined "so that the full record of the Pope's actions during the Holocaust may finally be known."

The Vatican's saint-making Congregation has voted in favor of a decree recognizing Pius' "heroic virtues," a major hurdle in a long process toward sainthood that began in 1967.

"We urge Pope Benedict XVI to suspend the sainthood process for Pope Pius XII for the sake of historical truth and the deepening friendship between the Catholic Church and the Jewish people," said Abraham Foxman, the league's national director and a Holocaust survivor.

"While we understand that the process of sainthood is an internal matter for the Church, the issue of what Pius XII did or did not do to help save Jews during the Holocaust is a profound question that must be resolved first for the sake of the Jewish-Catholic relationship," he said in a statement.

According to the Vatican Web site, it is up to the Pope to decide the "liberalisation" of access to documents on the basis of an entire papacy. Documents have been "liberalised" up until -- and including -- the papacy of Pius XI, which ended in 1939.

If the documents are "liberalised," only scholars are granted access to the papers.

If German-born Pope Benedict approves the Congregation decree, as expected, Pius XII would be officially given the title "venerable." The Vatican would then move toward beatification by looking for miracles performed by the late Pope.

The pontificate of Pius has been one of the trickiest problems in postwar Roman Catholic-Jewish relations.

Jewish groups have accused Pius of being indifferent to the Holocaust and diplomatic ties between the Vatican and Israel were briefly tested last month over a depiction of him at a state Holocaust memorial in Israel.

Before being elected Pope in 1939, Pius XII was Cardinal Eugenio Pacelli. He served as the Vatican's ambassador to Germany in 1917-1929 and was Vatican secretary of state in 1930-1939. Pius died in 1958.

The Vatican maintains that Pius did not speak out against the Holocaust more forcefully because he was afraid of worsening the fate of Catholics and Jews and worked behind the scenes to save Jews.

Jewish groups have pressed the Vatican for years to either freeze the sainthood process of Pius XII or shelve it altogether for fears that it would harm Catholic-Jewish relations.

Pope Benedict is in Brazil for a five-day visit to reinforce the Roman Catholic message on traditional family values and try to halt a tide of defections to Protestant religious groups.