Liberal Judaism chief executive Rabbi Danny Rich condemned religious coercion and sectarianism in his address to the movement's biggest biennial conference, held in Gloucestershire.
Addressing an audience of over 300, he said that some religious followers have "declared in both word - and frequently more tragically in deed - that democracy is in opposition to the values and practices of religious faith."
He also hit out at what he called the "special pleaders", citing as examples requests by Jewish schools for exemption from the Race Relations Act and the wish of Catholic adoption agencies to discriminate against same-sex couples.
"Liberal Judaism - conscious of its wider social responsibility - has much to offer a multicultural society," Rabbi Rich added.
Echoing his sentiments, Reform Movement executive director Rabbi Shoshana Boyd Gelfand said it was essential to find a middle ground between fundamentalism and apathy, remaining passionate about Jewish tradition while being open to the modern world.
Also discussed were plans to set up a Liberal Judaism think tank, covering isues such as Jewish status and tikkun olam (acts of kindness).
Guests also learned about the aid work of World Jewish Relief, which Liberal synagogues are being encouraged to support through Kol Nidre appeals.
Simon Benscher, Simon Frais, Penny and Mike Beral, Ivor Miskin and Hilda Schindler received the Chairman's Award, recognising exceptional service to the movement.