Chancellor Olaf Scholz joined thousands of people protesting against an alleged far-right plan to deport “unassimilated” immigrants from Germany.
Senior politicians from the Alternative for Germany (AfD) party reportedly met neo-Nazi activists to discuss such a proposal in a hotel near Berlin late last year.
At the meeting, the Austrian leader of the far-right Identitarian movement, Martin Sellner, reportedly proposed a project of “remigration” which would see “unassimilated” immigrants forced to leave Germany – even if they had citizenship.
Investigative portal Correctiv said Roland Hartwig, personal assistant to the leader of the AfD, was there.
Mr Scholz and foreign minister Annalena Baerbock were in Potsdam, just outside Berlin on Sunday – the area they both represent in the German parliament.
Ms Baerbock said she was there as someone who “stands for democracy and against old and new fascism”.
“These plans are reminiscent of the darkest chapter of German history,” said Potsdam Mayor Mike Schubert.
There was also a demonstration at the Brandenburg Gate in the German capital.
Read more:
How far-right has grown into greatest threat to Germany’s democracy
German far-right politician ‘danced’ on Holocaust memorial
The AfD, currently second in national polls, said it had no organisational or financial links to the event last year.
Members said to have attended did so in a purely personal capacity, it added.
Germany has European Parliament elections in June.
Those are followed by state elections in September in three eastern regions where the AfD is strong.
The AfD is under investigation by security authorities in several German states and risks being declared an extremist organisation, which could lead to it being banned.
The party denies it is extremist or racist.