Thousands of mourners gathered in Jerusalem on Sunday afternoon for the funeral of Menachem Mendel Taub, one of Israel's best-known Chassidic rabbis who died aged 96.

The Kaliver Rebbe, a survivor of Josef Mengele's experiments at Auschwitz, died earlier in the day.

The seventh rebbe in a direct paternal line stretching back to Yitzchak Izak of Kaliv, Rabbi Menachem Mendel was born in 1923 in Transylvania. In 1944, he was deported to Auschwitz, along with his six brothers and sisters, all of whom were subsequently murdered by the Nazis.

Alone among Chassidic rebbes, Rabbi Taub was distinctive for his lack of facial hair.

This was a result of him having been experimented on in Auschwitz by Dr Josef Mengele, the infamous “Angel of Death”, who performed sadistic genetic experiments on camp inmates.

The procedures he was forced to undergo left him unable to grow facial hair or father children.

Rabbi Taub was able to reunite with his wife after the end of the war. They moved to America in 1947 and emigrated to Israel in 1962, rebuilding the Kaliv Chassidic sect.

He was an active participant in Jewish outreach and Holocaust memorial initiatives, promoting the idea of reciting the Shema, one of Judaism’s key prayers, as a way of remembering those who were killed.

Both Israel’s Prime Minister Benjamin Netanyahu and President Reuven Rivlin paid tribute to the Kaliver Rebbe in the wake of the news of his passing.

Mr Netanyahu expressed “deep sorrow”, describing how he had “survived the Nazi atrocities during the Holocaust and was dedicated to the rebuilding of the world of Torah in Israel and the diaspora.”

He also praised his “tireless work promoting Holocaust remembrance.”

President Rivlin described the Kaliver Rebbe as “an inmate at Auschwitz who dedicated his life to the victims' memory.

“His work has particular resonance at present as we redouble our commitment to remember and never forget.”

Rabbi Taub once described why promoting the recital of the Shema was so important to him: “A few hours before we were liberated [from Bergen Belsen], the Nazis took many Jews and threw them into the fire.

“I cried out the Shema Yisrael and I said ‘Ribbono shel Olam [Creator of the World], this might be, chas v’shalom [God forbid], the last time I will be saying Shema Yisrael.

“Soon I will be with the rest of my family in Heaven. If you give me life, then I promise You that I will say time and again Shema Yisrael, declaring Your eternity with those who will outlive the war.”

The rebbe’s step-grandson, Rabbi Yisrael Mordechai Yoel Horowitz, has been announced as the new leader of the Kaliv Chassidus.