Rabbi Avraham Moshe (Aba) Dunner, executive director of the Conference of European Rabbis, died at his London home on Sunday.
He was 74 years old.
The Conference said that Rabbi Dunner had over many years been the leading activist for the cause of Orthodox Judaism in Europe and was widely loved and respected across the Jewish World.
He had been seriously ill since returning from the United States shortly after Passover.
Born in Konigsberg (today Kaliningrad in Russia) in 1938, he was the eldest son of the Rosh Beis Din of the Union of Orthodox Hebrew Congregations of the United Kingdom, Rabbi Yosef Zvi Halevi Dunner.
Called to assist the Conference of European Rabbis by its late president and Chief Rabbi of the United Kingdom, Lord Immanuel Jakobovitz, Rabbi Dunner was at the heart of the building and strengthening of Jewish institutions in Europe for over 20 years.
In a statement, Rabbi Arye Goldberg, Deputy Director of the Rabbinical Centre of Europe (RCE), said: "It is with great sadness that we learnt of the passing of Rabbi Aba Dunner. He was a pillar of the British and European Jewish community and his devotion to Klal Yisrael was enormous. The Rabbinical Centre of Europe mourns a dear colleague and know that his presence will be sorely missed by all those who are involved with Jewish life in Europe. Our condolences go to his family and may The Omnipresent comfort them among the mourners of Zion and Jerusalem".