Abraham Skorka, a biophysicist and rabbi who held inter-religious talks with the Pope when he was archbishop of Buenos Aires, said he discussed the issue with the pontiff when staying at the Vatican in September.
“What we said to each other was between us, but I believe that, yes, he will open the archives...The issue is a very sensitive one and we must continue analyzing it,” Skorka told The Sunday Times.
Pope Pius XII led the Catholic Church from 1939 until 1958 and has been widely criticized for staying silent over the Holocaust, in which six million Jews were killed.
The former pontiff is on the path to sainthood, although Pope Francis may open up the archives before a final decision on Pope Pius XII’s canonization is made.
“The Pope is consistent with all he said as a cardinal, and as pope he will undoubtedly make happen what he said he would do when he was a cardinal," added 63-year-old Skorka, referring to a book the pair published together in 2010.
In the book, On Heaven and Earth, the future pope said: “Opening the archives of the Shoah [Holocaust] seems reasonable”.
“Let it be seen if they could have done something [to help] and until what point they could have helped...the truth has to be the goal,” he wrote, quoted in The Sunday Times.
The revelation comes ahead of Pope Francis’ expected trip to Israel in May and three months after the Italian government said it was considering making Holocaust denial a crime.
The Senate’s Justice Committee in October approved a bill to criminalize Holocaust denial, Italian media reported.