Lord Rabbi Sacks has warned of the prospect of Europe becoming “judenrein” – “free of Jews” - pleading for European leaders to “stop it now while there is still time”.

The Emeritus Chief Rabbi said that “in every single country of Europe, without exception, Jews are fearful for their or their children’s future”.

“If this continues, Jews will continue to leave Europe, until, barring the frail and the elderly, Europe will finally have become Judenrein.”

Lord Rabbi Sacks made the comments in an address to a conference, entitled The Future of the Jewish Communities in Europe, at the European Parliament in Strasbourg.

He urged Europeans not to think of this as simply a Jewish issue, referring to the appearance of antisemitism in a national culture as being: “The first symptom of a disease, the early warning sign of collective breakdown”.

He warned: “If Europe allows antisemitism to flourish, that will be the beginning of the end of Europe.

“We make a great mistake if we think antisemitism is a threat only to Jews.

“It is a threat, first and foremost, to Europe and to the freedoms it took centuries to achieve.

“The hate that begins with Jews never ends with Jews. That is what I want us to understand today. It wasn’t Jews alone who suffered under Hitler. It wasn’t Jews alone who suffered under Stalin. It isn’t Jews alone who suffer under ISIS or Al Qaeda or Islamic Jihad.”

Lord Rabbi Sacks said anti-Zionism could be regarded as antisemitism.

“Antisemitism means denying the right of Jews to exist as Jews with the same rights as everyone else. The form this takes today is anti-Zionism.

“It is easy to hate, but difficult publicly to justify hate. Throughout history, when people have sought to justify antisemitism, they have done so by recourse to the highest source of authority available within the culture.

“In the Middle Ages, it was religion. So we had religious anti-Judaism. In post-Enlightenment Europe it was science. So we had the twin foundations of Nazi ideology, Social Darwinism and the so-called Scientific Study of Race.

“Today the highest source of authority worldwide is human rights. That is why Israel—the only fully functioning democracy in the Middle East with a free press and independent judiciary—is regularly accused of the five cardinal sins against human rights: racism, apartheid, crimes against humanity, ethnic cleansing and attempted genocide.”

The highly respected author and philosopher stressed the perilous consequences of antisemitism in Europe, telling the conference:

“If Europe lets itself be dragged down that road again, this will be the story told in times to come.

“First they came for the Jews. Then for the Christians. Then for the gays. Then for the atheists. Until there was nothing left of Europe’s soul but a distant, fading memory.

“You know where the road ends. Don’t go down there again. You are the leaders of Europe. Its future is in your hands.

“If you do nothing, Jews will leave, European liberty will die, and there will be a moral stain on Europe’s name that all eternity will not erase.”

Among those attending the conference were Cecilia Wikstrom, Swedish MEP and Vice Chair of the European Parliament's working group on antisemitism, Rabbi Pinchas Goldschmidt, President of the Conference of European Rabbis, and the philosopher Bernard Henri-Levy.