The head of the Rabbinical Centre of Europe, Rabbi Menachem Margolin, has argued that Brexit could lead to an increase in antisemitism across Europe.
Rabbi Margolin, whose organisation represents over 800 rabbis across the continent, said: "The EU is today much weaker. The UK in particular was a strong advocate for freedom of religion and in the fight against antisemitism. We have lost an important voice here in Brussels and across the continent as a whole.
"Sadly the beneficiaries of this chaos in Europe are the radical parties of the far left and right."
Rabbi Margolin connected the Brexit effect to the darker periods of European history.
He said: "History teaches us that nationalism and radicalism brings with it nationalistic fervour, dark language and antisemitism. It also brings attacks on the Jewish way of life such as ritual slaughter and circumcision.
We were shocked… I think it is a terrible mistake
"I'm urging governments across Europe to not lose focus and to re-double their efforts in fighting antisemitism wherever it rears its ugly head."
Sammy Stein, one of the founding members of Glasgow Friends of Israel, said he was "despairing" at the vote.
The 69-year-old IT consultant said his community was "very concerned.
"When you see the way David Cameron has decided to walk away from the problem and leave it in the hands of very inexperienced politicians, it's hard to see how UK will deal with negotiations.
"There's going to be a very long period of uncertainty while the UK negotiates its relationship with the EU, and I'm worried about how Scotland will survive if it exits the UK."
Douglas Ryan, who represents Gibraltar on the Board of Deputies, said with a "very hostile" Spanish government next door and an economy dependent on Europe, his compatriots were scared.
"It would be madness for Gibraltar to want to exit Europe, so we expressed our worry and fear last Thursday." But he said Gibraltarians, 95 per cent of whom voted for Remain, were "resilient, innovative and pragmatic. We have had setbacks in the past. We survive."
In Germany, Frankfurt resident Sacha Stawski, head of the pro-Israel watchdog Honestly Concerned, said: "Ultimately it is going to be bad for us, of course. As soon as people start realising the economic downturn they start looking at the Jews again. Plus, the more open a society is, the more welcoming they are towards us."
Director of the Jewish Film Festival Berlin-Brandenberg, Nicola Galliner, whose parents fled Nazi Germany to England, said she was "really shocked".
Relatives in England "are asking me how they can get German passports for their children so they can work in Europe. I think it is a terrible mistake".
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