Government statistics released earlier this month showed that the number of antisemitic and anti-foreigner incidents rose in Germany last year, despite an overall drop in politically motivated crimes.
The number of attacks against Jews rose by 10 per cent to 1,646 in 2018, and the number of reported violent attacks against Jews also rose from 37 to 62.
Felix Klein told the Funke newspaper group: "My opinion has unfortunately changed compared with what it used to be.
“I cannot recommend to Jews that they wear the skullcap at all times everywhere in Germany,” he said. He did not elaborate on what places and times might be risky.
Mr Klein suggested police, teachers and lawyers should receive more training to recognise antisemitism.
“The internet and social media have largely contributed to this — but so have constant attacks against our culture of remembrance,” he said.
He said while 90 per cent of attacks are carried out by the far-right, those carried out by Muslims are connected to Arab TV stations "that convey a fatal picture of Israel and Jews".
Last year, Germany’s main Jewish leader, Josef Schuster, said he would advise people visiting big cities against wearing Jewish skullcaps.
In the same year, Angela Merkel denounced a “different type of antisemitism” that she said Arab refugees had brought to Germany, following an assault on two young men wearing Jewish skullcaps.
The German chancellor said she was “saddened” her country had not been able to snuff out antisemitism for good, and lamented the fact that Jewish schools, kindergartens and synagogues needed police protection.
“We have refugees now, for example, or people of Arab origin, who bring a different type of antisemitism into the country,” she said during the interview. “But unfortunately, antisemitism existed before this.”
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