The success of the far-right National Front in France's regional elections has caused shock across Europe, with attention focusing on the apparently growing support for the party among French Jews.
Roger Cukierman, president of the French Jewish umbrella organisation, Crif, said it was impossible to know how many members of the community had voted for Marine Le Pen's candidates, but that it was necessary to urge Jews not to vote for the party in Sunday's second round.
The National Front won almost 28 per cent of the vote nationally in last weekend's regional polls, finishing top in six of the 13 regions.
Mr Cukierman said: "Jews are like all the other French people; they have the same problems about the economy and security. Unfortunately, there are more and more French people choosing to vote for the NF, without realising that, within this party, there are principles and values that are not those of the Jews.
"Most notably it is a populist and xenophobic party, in the tradition of the French extreme right, the consequences of which we have experienced during the Vichy period."
There are problems from all sides, we feel surrounded
Crif has published a number of communal briefings encouraging people to vote en masse to block Ms Le Pen's party from power. France's chief rabbi, Haim Korsia, called for a "civic uprising" of voters, "to breathe life into democracy in these particularly troubled times for the nation".
Community leaders may have reason to fear growing support among French Jews for the party whose founder, Jean-Marie Le Pen, has a series of convictions for racism and antisemitism, and called Nazi gas chambers a "detail" of the Holocaust.
A report published by a French polling company last year claimed 13.5 per cent of Jews had voted for Ms Le Pen in the 2012 presidential elections, a substantial increase on the 4.3 per cent who voted for her father in 2007.
Mr Cukierman admitted that morale was low within the community.
He said: "There's a feeling of pressure, a feeling of not being like other citizens because there is an environment of hostility, which comes from several sides.
"We have a situation where we have lots of reasons to be afraid. Between the threat of Daesh, which has already committed many murders in France; violent acts committed by youths from the suburbs; anti-Zionism from the extreme-left which develops boycotts; and from a higher level, the European Union calling to label products from the Israeli settlements.
"We have the impression that there are problems from all sides, we have a feeling of being surrounded. But I don't think the NF is a solution to our problems, it is just an additional problem."
Earlier this year, Mr Cukierman said Ms Le Pen was "irreproachable" for having not made any antisemitic comments throughout her career and distancing herself from her father, Jean-Marie.
But, following Crif's criticisms this week, she responded in a radio interview by saying that the Jewish organisation received subsidies from the government. She appeared to infer that the supposed payments influenced Crif and others to back the current administration.
But Mr Cukierman dismissed her claims as "simply false" and added: "We do not receive one centime from the government nor any public authority."
In response to Sunday's results, President Francois Hollande's Socialist party said it would tactically withdraw some candidates for the second round in an attempt to push votes to former French president Nicolas Sarkozy's Republicans and centre-right parties.
Racism watchdog SOS Racisme also launched a campaign calling on the French to vote against the NF.
Ms Le Pen is nonetheless expected to win the election in the northern region of Nord-Pas-de-Calais-Picardie, and her niece, Marion Maréchal-Le Pen, is expected to win in Provence-Alpes-Côte-d'Azur.
The 25-year-old has become the party's poster girl. She was the youngest MP in France at the age of 22 and won around 40 per cent of the vote last Sunday.
She is seen as being ideologically closer to her grandfather.
