The chief rabbi of Rome has expressed scepticism about the “ready-made files and easy conclusions” proposed by the Vatican on the role of controversial wartime pope Pius XII during the Holocaust.

The Vatican threw open the archives of Pius’ 20-year papal reign on Monday, allowing historians access to documents that may shed light on the Holy See’s knowledge and diplomacy surrounding the Holocaust.

Johan Ickx, one of the Vatican archives’ directors, provided an overview of what researchers could expect to find and a commentary on certain select documents in Vatican News.

He drew attention to around 170 files on “Jews” that contain the names and pleas for help of some 4,000 people.

But Rome’s chief rabbi Riccardo Di Segni said it was important to let historians conduct their own research.

Mr Ickx wrote that while “a majority of requests for help are from Catholics of Jewish descent, the names of Jews are not lacking”.

He believed that the documents would “highlight how many and what efforts were made to try and respond to pleas for help from the persecuted”.

The Vatican had been under pressure to open the archives earlier than the usual 70 years after the end of a papal reign, while Holocaust survivors are still alive.

The Vatican Apostolic Archives, which until October were known as the “Secret Archives” contain up to 2 million pages of documents from Pius XII’s papacy.

“After saying that it will take years of study, now conclusions have come out on the first day like a rabbit emerges from a magician’s hat. Please let historians work,” Riccardo Di Segni, the chief rabbi, told Italian news agency Ansa.  

Among the documents quotes in the Vatican News, is a handwritten note by Pius XII questioning the wisdom of newswires reporting on the deportation of Rome’s Jews in October 1943.

“Is it prudent that the press service sends this news?” the note reads. “Not really,” reads the response of another high ranking Vatican official.

Mr Ickx commented that the exchange revealed Pius XII’s awareness that “it did not help to wake sleeping dogs, especially not Nazis, to humanitarian actions initiated by the Apostolic Palace”.

But Rome’s rabbi said that “it doesn’t take much to realise that these scarce revelations will prove to be a boomerang for apologists” of the Holy See’s silence during the Holocaust.

He claimed “Pius XII had no will to stop the train of October 16,” which deported 1,022 Jews from the Italian capital and that what aid was provided “was well targeted to protect the baptised”.

Pius XII’s papacy ran from 1939 until 1958, and he never publically condemned the Holocaust, despite historians agreeing that the Vatican was aware of the murder of Jews across Europe. Debate hinges on whether the Vatican remained too silent during the Holocaust.

There is debate in Italy whether an intervention by the Holy See might have slowed or made the Nazis reconsider the deportation of Roman Jews in October 1943, which they had occupied after Italy capitulated in September.

The American Jewish Committee’s representative in Italy Lisa Palmieri-Billig told La Stampa that the most complex aspect of research would be to shed light on the “silence of Pope Pius on the Holocaust, a silence that inexplicably continued even into the post-war years of his long pontificate”.

Holocaust researchers will be among the first to gain access, including some from the United States Holocaust Memorial Museum.