The Chief Rabbi, Lord Sacks, has called for an “intellectually open, humble and tolerant religiosity” as a bulwark against fundamentalism.

In a keynote lecture to the religious think-tank Theos in London last week, he said: “Religion is going to grow in strength in the 21st century and a very great deal will depend on what kind of religion it is.

“At the moment, the fastest growing religions in the world are those who take an adversarial stance towards society, religions that challenge liberal democratic freedoms, and that is bad news.”

Worse, was that various global conflicts which were political had become “religionised”, he said.

“I believe we have no choice but to articulate an intellectually open and humble and tolerant religiosity, as the only strong enough defence for some of the religiosity that is coming our way with the force of a hurricane,” he said. But if the fundamentalists won the challenge he said: “I wouldn’t hang around too long.”

Lord Sacks called for a new dialogue between religion and science, an alliance between science and religion to combat global warming and “respectful conversations” between religious groups and secular humanists.

He also said that the indigenous population of Europe was dying because people did not want to make the sacrifices necessary to have children.

“We are undergoing the moral equivalent of climate change and no one is talking about it,” he said.

In contrast, the more religious the family — whether Jewish, Christian or Muslim — the more children it had, he argued.

In a question and answer session, he also expressed his confidence that Islam would follow Christianity and Judaism in recognising the separation of religion and power. “But there’s no quick way of getting there. It’s quite a difficult and painful process,” he said.