The Israeli ambassador to Germany has said he is concerned for Jews in Germany, against the background of what he says is rising anti-semitism there.
Michael Regener was convicted of spreading racial hatred
In a newspaper interview, Shimon Stein said the number of neo-Nazis in Germany had also increased.
The interview appeared as neo-Nazi sympathisers gathered outside Berlin's Tegel Prison to demand the release of a singer jailed for three years.
A court ruled that Michael Regener's band was spreading racial hatred.
Mr Stein told the Neue Osnabruecker Zeitung he believed there was a greater willingness on behalf of neo-Nazis to use violence.
"I have the feeling that Jews in Germany do not feel safe. They are not always able to practise their religion freely," he said.
He said tightened security had been put in place around synagogues and other institutions.
He said the fact that neo-Nazis had made gains in recent regional elections showed that these tendencies could no longer be dismissed as marginal.
More than 1,200 neo-Nazis from across Europe were due to march on Tegel Prison on Saturday to demand Regener's release.
In March 2005, a German court rejected an appeal by the singer - aka "Lunikoff" - to have his sentence repealed.
Germany has strict laws against promoting Nazism or using Nazi symbols.
Three years ago, a Berlin court found the band Landser - meaning "foot soldiers" - guilty of spreading hatred of Jewish people and foreigners in Germany.
Landser's CD titles include The Reich Will Rise Again and Get The Enemy.
In February 2005, thousands of neo-Nazis marched through Dresden on the 60th anniversary of the allied bombing of the city.
It was one of the biggest far-right demonstrations in Germany's post-war history.
Last year the far-right National Democratic Party (NPD) won 9% of the vote in Saxony, giving it seats in a German state assembly for the first time since 1968.
In May, German Interior Minister Wolfgang Schaeuble urged extra vigilance from the public to help tackle a rise in far-right extremism.
He said there should be no "no-go areas" for foreigners, as he presented an official report showing a rise in neo-Nazi violence in 2005.