VATICAN CITY, November 8, 2008 -- Pope Benedict XVI Saturday returned to the defence of one of his predecessors, Pius XII, accused of passivity during the Nazi genocide of Jews, saying the controversy was excessive and one-sided.

There are moves to beatify Pius XII, who died 50 years ago, the first step towards canonisation but the plans have been criticised by Jewish groups. "These recent years, when Pius XII has been talked about, attention has been excessively concentrated on a single issue, moreover it is treated in a rather one-sided way," Benedict told participants at a symposium on Pius XII in remarks made public by the Vatican.

That "has prevented a fair approach to the figure of great historical and theological importance that was Pius XII," the pontiff said, adding that his predecessor had bequeathed "a precious legacy" to the Roman Catholic Church.

In early October Benedict had defended the memory of Pius XII and indicated he wished him to be beatified in the near future. But he did not sign the decree proclaiming his "heroic virtues", a necessary step in the beatification process.

After his remarks the grand rabbi of Haifa in Israel, Shear Yashuv Cohen, said Pius XII should not be "taken as a model" and should not be "beatified because he did not raise his voice in the face of the Holocaust."

At the end of last month Benedict said after receiving the president of the international Jewish committee for inter-religious affairs, rabbi David Rosen, that he was studying "seriously" the opening of the archives relating to Pius XII before beatifying him.

The same day Vatican spokesman Father Federico Lombardi said that it would be six or seven years before the secret archives were opened because of the large amount of work involved.

Critics accuse Pius, who headed the Roman Catholic Church from 1939 to 1958, of having remained silent during the Holocaust that killed an estimated six million Jews.

John Paul II was the first pope to pay an official visit to a synagogue and make an official trip to Israel.

John Paul also was the first to pray at the Auschwitz death camp in his native Poland and to formally repent for the Catholic Church's failure to adequately recognise and react to the Holocaust.

Benedict has sometimes stumbled to improve inter-faith relations.

Most recently he allowed the reintroduction of a controversial Good Friday prayer calling for the conversion of Jews.

The history of Christian persecution of Jews, including genocide, exile, pogroms, crusades and discrimination, goes back 2,000 years.