Israeli and Vatican historians met for the first time on Sunday to discuss the current state of research into Pope Pius XII and his Holocaust-era conduct. The gathering at the Yad Vashem Holocaust memorial signals a growing willingness on the part of both Israeli and Vatican officials to try to resolve one of their most sensitive disagreements - the pope's action or inaction during the Nazi genocide. Most Jews believe that Pius was partly to blame for the scope of the tragedy, due to his failure to speak out publicly against the Nazi atrocities or attempt to mobilize Catholics in Germany and elsewhere to stop it. The Vatican has struggled to defend its wartime pope as it pushes his sainthood cause, insisting that Pius spearheaded discreet diplomacy that saved thousands of Jews. A symbol of the dispute is a caption of a photo of Pius at Yad Vashem's museum that says he did not protest the Nazi genocide of Jews and maintained a largely "neutral position." The Vatican protests the wording. "The complex historical issues that will arise during the workshop touch on basic human values and questions of morality," said Yad Vashem director Avner Shalev. "Serious academic research, the goal of which is to uncover the truth, must rest on documentation," he added. The two-day academic workshop began shortly before Pope Benedict XVI announced he would visit Israel from May 8-15, the second official trip by a pope to Israel. Pope John Paul II made the first such pilgrimage in 2000. Israel has encouraged the Vatican to open its wartime archives to allow researchers to look for concrete examples of Pius's actions. But the Vatican has denied access to major parts of its archives, including wartime papers. Shalev said Sunday he was pleased to learn that Benedict had instructed the archive to speed up the process of cataloging the material and hoped it could now be completed in three to four years. Yad Vashem said Shalev was informed of the development by Vatican archive officials and people who were in direct contact with the pope. Israel and the Vatican established diplomatic relations in 1993 after hundreds of years of strife between Catholicism and Judaism. Though ties have warmed considerably in recent years, many sensitive issues remain unresolved. The past month has been particularly strained. Israel was offended when senior Vatican Cardinal Renato Martino said during Israel's recent military campaign to stop rocket fire from the Gaza Strip that Gaza resembled a "big concentration camp." Israelis were also upset when the German-born pope reinstated an excommunicated bishop who had questioned the extent of the Holocaust, saying only 200,000 or 300,000 Jews were killed and that none were gassed. Benedict later condemned Bishop Richard Williamson's remarks and spoke out against anti-Semitism. The Vatican's ambassador to Israel, Monsignor Antonio Franco, said Sunday that the workshop marked a "new phase" in relationships and a rebuilding of trust. "I think it can be clear that one cannot be a Catholic if he denies the Shoah," Franco said.