Pope Benedict XVI has, for the first time ever, publicly defended Pius XII's controversial Second World War era activities, saying his "noble" and "beloved predecessor" did all he could to save Jews from Nazi and fascist persecution.

"Wherever possible he spared no effort in intervening in their favour, either directly or through instructions given to other individuals or institutions of the Catholic Church," the 81-year-old Pope told participants of a Rome symposium on 18 September at Castel Gandolfo.

The three-day gathering, sponsored by the US-based Pave the Way Foundation (PTWF) that works to improve relations between faith communities, sought to reveal new "eye-witness" documentation regarding Pius XII's activities concerning the Jews. Most of the "eminent scholars" in the group, as the Pope called them, held positive views of Pius XII, who was Pope from 1939 to 1958. But organisers said "dozens" of scholars who have criticised Pope Pius were also invited, though representatives of at least three Jewish organisations reportedly declined the invitation.

Pope Benedict applauded the PTWF for drawing attention to his predecessor's "many interventions" on behalf of the Jews. And he endorsed their view that these were "made secretly and silently". He argued that this was the only way "to avoid the worst and save the greatest number of Jews".

But it is precisely this claim that has long divided scholars. "Even if one is to accept that [Pope Pius] wisely held his tongue,"  wrote John Cornwell recently in a new introduction to his 1999 book, Hitler's Pope, "it was incumbent on him to offer an explanation to the world" after the war, "in light of the scandal he thereby occasioned" by his silence. Mr Cornwell, considered the leading critic of Pius XII's wartime efforts, said, "He not only failed to do this, but claimed he had been constantly outspoken."

Pope Benedict implied that such criticisms of his "courageous and paternal" predecessor were motivated by "ideological prejudices" and levelled in bad faith.

By contrast, he said participants of the PTWF symposium had "analysed without bias the events of history" and concerned themselves "only with the truth".  

Many saw the German Pope's comments as a further public endorsement of efforts to beatify Pius XII, whose cause has been hindered over his much debated wartime activities.  Supporters of the cause, including the man promoting it, Fr Peter Gumpel, said they were "sure" that "sooner or later" Pope Benedict would sign the decree to advance Pius XII's beatification process.

"Fifty years have passed since his pious death," Benedict XVI recalled. He said he hoped this anniversary year would be "an opportunity to promote in-depth studies" of the late pope's life "in order to come to know the historical truth, overcoming every remaining prejudice".

Mr Cornwell said that Hitler's Pope was the first, and remains the only, "full non-hagiographical" biography of Pius XII. He said all other scholarly works have concentrated almost exclusively on the wartime silence rather than his entire life. "It is nothing short of extraordinary that for a man who is being promoted as a saint by the Vatican no full and scholarly life exists other than my own."