French President Emmanuel Macron has announced new measures to tackle anti-Semitism, following a spate of attacks.
He told Jewish leaders that France would recognise anti-Zionism - the denial of Israel's right to exist - as a form of anti-Semitism.
He also said parliament would vote on a new law to tackle hatred on the internet.
On Tuesday Mr Macron visited a Jewish cemetery near Strasbourg where graves were desecrated with Nazi symbols.
On the same day, thousands of people joined rallies across France in support of the Jewish community.
Addressing an annual meeting of Jewish organisations on Wednesday, Mr Macron said anti-Semitism in France and other Western countries had reached its worst levels since World War Two.
Among a series of new measures, he said the government would act to dissolve three extreme-right groups - Bastion Social, Blood and Honour Hexagone and Combat 18 - which he said fuelled hatred and promoted discrimination.
Mr Macron added: "Anti-Zionism is one of the modern forms of anti-Semitism. This is why I'm confirming that France will put forward the definition of anti-Semitism as drawn by the International Holocaust Remembrance Alliance."
In recent months, France has witnessed a series of high-profile anti-Semitic attacks.
In the past week vandals defaced portraits of the late Holocaust survivor and French minister Simone Veil, scrawled the German word for "Jews" on a Parisian bakery and cut down a tree planted in memory of a Jewish youth tortured to death by an anti-Semitic gang.
A prominent French philosopher, Alain Finkielkraut, was also verbally attacked for being Jewish as he walked past a recent "gilets jaunes" (yellow-vest) protest in Paris.
During his visit to the Jewish cemetery in eastern France where nearly 100 graves were desecrated, President Macron said: "Whoever did this is not worthy of the French republic and will be punished."
The number of anti-Semitic crimes reported in France, which is home to the largest Jewish population in Europe, increased by more than 70% - from 311 in 2017 to 541 last year.
The tally is not the worst France has seen in the past two decades, and follows a two-year dip in attacks, BBC Paris correspondent Lucy Williamson reports.
However, anti-Semitic violence is believed to be spreading from the old prejudices of the far-right, to radical Islamists and far-left groups, our correspondent adds.