Andreas Geisel, the Berlin interior senator, said the authorities had to strike a balance between the right to freedom of assembly and the need to protect people against infection.
“We are still in the middle of a pandemic with rising infection figures,” he said, Reuters reported.
Germany has managed to keep the number of COVID-19 cases and deaths relatively low compared with some other large European countries, but the number of new daily cases has been rising steadily since early July and has accelerated in recent weeks.
About 20,000 people, included libertarians, constitutional loyalists, far-right supporters and anti-vaccination activists, marched in Berlin on Aug. 1.
Geisel said the organizers of that protest had deliberately broken the rules they had previously accepted in talks with police, including wearing masks and maintaining social distancing.
“Such behavior is not acceptable. The state cannot be given the runaround,” he said, adding he did not want Berlin to be a stage for conspiracy theorists and right-wing extremists.
If crowds still gather despite the ban, the police will intervene, he said.