An Israeli cabinet minister stepped into a row with the Vatican today, saying it was "unacceptable" to consider canonising Pius XII, who was pope during the second world war and has been criticised by some for not publicly opposing the Holocaust.

In an interview with the Israeli newspaper Ha'aretz, Isaac Herzog, Israel's social affairs minister, who is responsible for relations with Christian communities, said efforts to turn Pius into a saint were "an exploitation of forgetfulness and lack of awareness".

He accused Pius of having kept silent during the war. "Throughout the period of the Holocaust, the Vatican knew very well what was happening in Europe," Herzog told the paper. "Yet there is no evidence of any step being taken by the pope, as the stature of the Holy See should have mandated ... Instead of acting according to the biblical verse 'thou shalt not stand against the blood of thy neighbour' the pope kept silent - and perhaps even worse."

His comments come at a time when some in the Vatican have been pressing for the current pope, Benedict XVI, to take the next step towards making Pius a saint by approving a decree recognising his "heroic virtues". Earlier this month the pope paid tribute to his wartime predecessor, but a Vatican spokesman said Benedict was now in a period of reflection about Pius. "It isn't right to submit him to pressures on one side or another," the spokesman, Father Federico Lombardi, said in Rome.

Benedict has defended Pius, saying he worked "secretly and silently" during the war and saved thousands by ordering churches and convents in Italy to hide Jews and by giving them false passports to escape.

Others have been more critical. One regular source of contention between Israel and the Vatican is a brief photo caption at Yad Vashem, Israel's Holocaust memorial in Jerusalem, which challenges Pius' wartime actions. The caption states that Pius, who was pope between 1939 and 1958, abstained from signing a 1942 Allied declaration condemning the extermination of Jews, and that he did not intervene when Jews were deported from Rome to Auschwitz. "Even when reports about the murder of Jews reached the Vatican, the Pope did not protest either verbally or in writing," it says. "His silence and the absence of guidelines obliged churchmen throughout Europe to decide on their own how to react."

Earlier this month the Vatican called on Yad Vashem to conduct a "new, objective and in-depth review" of the caption. However, although the Vatican has opened its archives to researchers for the period shortly before the war, the archives of Pius' papacy remain closed. Yad Vashem defended its caption saying it represented "the best research regarding this topic" and called for the Vatican archives to be opened.

Some of those in the Vatican who are pushing for Pius' beatification say the current pope should not visit Israel until the caption has been changed. "How can he go there knowing these captions are absolutely historically untrue?" Father Peter Gumpel, a German Jesuit who is leading the campaign for sainthood for Pius, said in an interview with the Associated Press in the Vatican City last week. "Catholics would be mortally offended."

Israel and the Vatican only established full diplomatic relations in 1993 and since then there have been other disagreements, over issues including the taxing of church property in and around Jerusalem and permits for Arab Christian clergy to travel through the occupied West Bank. Pope John Paul II visited Israel in 2000, the first pope to do so, but Pope Benedict XVI appears to have no plans to visit in the near future.

On Sunday, the Israeli president, Shimon Peres, said the row over the photo caption should not prevent a papal visit, though he too was critical of Pius. "We have reason to believe that Pius XII didn't do enough to save Jewish life. I don't want to pass judgement," Peres said. "If there is evidence then it should be checked carefully. The visit to the holy country is nothing to do with anger or disputes. It's holy all the time. It is holy for all of us."