Cardinal Tarcisio Bertone spoke at a gathering marking the 50th anniversary of Pius's death, ANSA, the Italian news agency, reported. He denounced a recent book with the title "Hitler's Pope."
''The representation of Pius XII as indifferent towards the victims of the Nazis ... or even as 'Hitler's Pope' is outrageous and historically unsustainable,'' Bertone said.
Immediately after the war, Pius was praised by many Jewish leaders for helping to hide Jews from the Nazis. They accepted his belief that he could do more good by working in secret.
But some later historians have taken a darker view of his wartime silence. The controversy has revived because Pius is a candidate for beatification, the final step before sainthood.
Bertone said that beatifying Pius is a "religious matter which must be respected by all."