Chancellor Olaf Scholz reminded Germans of their Nazi past on Wednesday as he called on citizens to reject the far-right Alternative for Germany (AfD) which is second in most national polls.
Hundreds of thousands of people have joined demonstrations across Germany against the AfD after a report that two senior party members had discussed plans for the mass deportation of citizens with foreign backgrounds - a term called remigration.
Addressing the Bundestag lower house of parliament after a special session marking the Holocaust and dressed in a black suit and tie, Mr Scholz said democrats must stand together and stop the shift to the right.
"The word 'remigration' is reminiscent of the darkest times in German history," Mr Scholz said.
"Those who remain silent are complicit," he said, adding he wanted voters to see the AfD for what it was.
Support for the AfD dipped slightly in a poll published this week following the protests but the party, which has a strong focus on migration, is still second in most polls before this year's European elections.
Mr Scholz also said that "Dexit", the idea of Germany leaving the European Union, which AfD co-leader Alice Weidel has talked about, would lead to "the greatest destruction of prosperity that could happen to Germany and Europe".
In an unusually combative speech during which he waved his clenched fists in the air, Mr Scholz argued for a stronger EU.
"If the world becomes even more difficult, for example if you look at what is possible in the US election, then the European Union must become all the stronger," he said, adding the bloc must complete a banking and capital market union.
Support for Social Democrat Scholz and his awkward three-way coalition with the Greens and pro-business Free Democrats (FDP) is hovering around record lows.
