A top EU official has warned that Europe faces a "huge challenge" in persuading Jews not to emigrate in response to anti-Semitism.
European Commission Vice-President Frans Timmermans suggested the issue was as urgent as the euro's troubles.
"In some [EU] states the majority of the Jewish community is not sure they have a future in Europe," he said.
France, with the EU's biggest Jewish community, has announced sweeping anti-terror measures after Islamist attacks.
French Prime Minister Manuel Valls said 2,680 new security-related jobs would be created, including 1,100 in police intelligence, over three years.
He pledged an extra €425m (£325m; $490m) in funds, saying 3,000 people were under surveillance in France. In addition, 7,500 French defence jobs due to be cut will now be saved.
On 9 January, an Islamist militant shot dead four Jewish men during a hostage-taking at a kosher supermarket in Paris.
He was subsequently killed by police as were two Islamist militants who earlier killed 12 people at the Paris offices of satirical magazine Charlie Hebdo, allegedly shouting that they were "avenging" cartoons of the Prophet Muhammad.
Speaking in Brussels, Mr Timmermans said about Jewish fears: "I think this is a huge challenge to the very foundations of European integration.
"We can talk till kingdom come about the euro, about internal markets, about whatever initiative we take, but if this fundamental value in European society, which is that there is a place for everyone whatever your creed is, whatever your background is, your race is, the choices you make in society if that is challenged we have to answer that challenge by a policy that offers hope and prospect[s] for everyone in European society."
Mr Timmermans also said he wanted to see a swift decision on the sharing of passenger name records and reinforcing the outside borders of the Schengen area - the 26 countries that have abolished internal passport controls.
Schengen, he said, should be seen as part of the solution, not part of the problem.
Not everyone in the European Parliament is happy about the sharing of passenger data and its possible implications for civil liberties, the BBC's Paul Adams reports from Brussels.
Mr Timmermans sought to reassure critics, saying anything that changed the open, tolerant nature of European society would play into the hands of terrorists.
UK Home Secretary Theresa May sought to reassure Britain's Jewish population earlier this week that everything was being done to protect them.