A Vatican exhibit marking 50 years since the death of Pius XII was to open Tuesday, just days after Pope Benedict XVI placed his controversial Nazi-era predecessor`s sainthood dossier on hold.

The show may help to dispel `malign interpretations` of Pius XII`s behaviour during the war years, when he was accused of being silent about the Holocaust and passive towards the persecution of Jews, Vatican historian Walter Brandmueller told reporters.

`Pius XII: The Man and the Pontificate` traces the life of Eugenio Pacelli, who was the Vatican`s envoy to Germany and Pius XI`s secretary of state before being elected pope in 1939.

The exhibit was created at the initiative of Benedict, said Brandmueller, who heads the Pontifical Committee for Historical Sciences.

Benedict said on October 9 that he hoped the process to beatify Pius XII -- the first step towards sainthood -- would `proceed happily.`

But the 81-year-old head of the Roman Catholic Church indicated to a Jewish delegation on Thursday that the process would have to wait six or seven years until sealed archive material on Pius`s wartime years became available.

Vatican Secretary of State Tarcisio Bertone defends Pius XII`s wartime record in a forthcoming book.

If Pius XII `had intervened publicly, he would have endangered the lives of thousands of Jews who, at his request, were hidden in the 155 convents and monasteries in the city of Rome alone,` Bertone writes.

The process of beatifying Pius XII, which was launched in 1967, has sparked bitter debate and tension between Catholics and Jews.

Last month, Shear-Yushuv Cohen, the Grand Rabbi of Haifa, Israel, spoke out against such an honour for the Italian pope, saying Pius XII `should not be seen as a model and he should not be beatified because he did not raise his voice against the Holocaust.`

Last month, the priest in charge of Pius`s case for sainthood, Father Peter Gumpel, said Benedict was hesitating over the beatification dossier out of concern to maintain `good relations` with Jews.

Benedict has to sign a decree, which has been on his desk since May 8, attesting to Pius`s `heroic virtues,` after which Gumpel must produce convincing evidence of a miracle -- usually a medical cure with no scientific explanation.

The exhibit, which runs until January 6 at the Vatican, will later travel to Germany and the United States.