The wartime past of Pope Benedict XVI threatened to overwhelm his peace mission to the Holy Land as the Vatican issued a denial that the pontiff had served in the Hitler Youth.

“The Pope has said he never, never was a member of the Hitler Youth, which was a movement of fanatical volunteers,” Federico Lombardi, a Vatican spokesman, said — contradicting statements the Pope has himself made about his involvement with the group. The Vatican denial came as Benedict’s trip sank deeper in controversy and recrimination, eclipsing the message of peace and reconciliation he has been pushing during his pilgrimage

Mr Lombardi said the Pope, as Joseph Ratzinger, a 16-year-old seminarian, served in an auxiliary air defence squadron “that had nothing to do with Nazism or Nazi ideology”. Venting frustration with the relentless focus on the Pope’s war years — a highly sensitive subject on a visit to the Jewish state — Mr Lombardi insisted that the Pope “never was in this movement of young people ideologically linked to Nazism”. The spokesman said that he felt compelled to respond “to the lies written by the media here and internationally”.

However, in a series of interviews in the 1996 book Salt of the Earth, the Pope, then still a cardinal, said that he had been drafted into the Hitler Youth, like so many other young Germans.

“When the compulsory Hitler Youth was introduced in 1941, my brother was obliged to join. I was still too young but later, as a seminarian, I was registered in the HY. As soon as I was out of the seminary, I never went back,” he said at the time.

The questions hanging over the wartime service of the Catholic leader have soured his visit to Israel, where Holocaust survivors still bear the tattoos and memories of the Nazi death camps and some have expressed unease at having the German Pope visit.

Many Israelis thought that the Pope’s visit to Yad Vashem, the Holocaust memorial commemorating the murder of six million Jews by the Nazis, lacked the necessary remorse expected from a German with his background.

“All that was asked of you was to say a short, authoritative and moving sentence. All you had to do was to express regret. That’s all we wanted to hear,” the daily Yediot Aharonot said. “After all, it is claimed that you appointed to your Church a priest who denies the Holocaust and as a boy, you were a member of the Hitler Youth.”

The controversy has deepened after the Pope reinstated a British-born bishop who denied the extent of the Holocaust, causing outrage in Israel. The Vatican also asked that the pontiff be allowed to sidestep a Yad Vashem exhibit criticising his wartime predecessor, Pius XII, for allegedly ignoring the plight of Europe’s Jews. The Vatican denies that interpretation of history and is working to declare Pius XII a saint.

While the Pope has insisted that his pilgrimage is non-political, he has been increasingly sucked into the conflict that has mired the region for decades. The pontiff walked out of an interfaith meeting in Jerusalem after a Palestinian cleric called on him to help to stop Israeli “crimes”.

But on a visit to the Dome of the Rock, an Islamic shrine standing on the ruins of the destroyed Jewish temple, the Grand Mufti of Jerusalem, Mohammed Hussein, also urged his visitor to work to end Israeli “aggression” against Palestinians.

“We look forward for your holiness’s effective role in putting an end to the ongoing aggression against our people, our land and our holy sites in Jerusalem, Gaza and the West Bank,” he said.

The Pope is due to visit a Palestinian refugee camp today, heralding yet more controversy.