City Hall authorized the regular leftist rally called Day of Wrath, which it had earlier banned seven times, but organizers said Friday that they still expect a police crackdown.
Previous Day of Wrath rallies, the first of which dates back to May, were dispersed by police, and the main organizer, Left Front leader Sergei Udaltsov, spent 15 days in jail over the event in December.
But the activists are allowed to stage a rally on the downtown Teatralnaya Ploshchad next Saturday, Udaltsov told Interfax on Friday.
Protesters also plan to march to a Kremlin public office on nearby Staraya Ploshchad to file a list of their complaints, which may result in new detentions because the march, unlike the rally, was not authorized by City Hall, Left Front said in an online statement Friday.
Moscow officials did not comment on their reasons for allowing the event. City Hall spokeswoman Gulnara Penkova did not respond to a request for comment Friday.
The move was possibly ordered by federal authorities, who are looking to discredit ex-mayor Yury Luzhkov, Yevgeny Minchenko, director of the International Institute of Political Expertise, a think tank, said Friday.
Previous Days of Wrath have mostly been focusing on city problems, linking most of them to Luzhkov, not his successor Sergei Sobyanin, who took office in October. Participants have often called for criminal charges against Luzhkov.
The decision is also in line with Sobyanin's softened stance on political protests, which already saw the City Hall authorizing another regular opposition rally that takes place on the 31st of each such month on Triumfalnaya Ploshchad.
The event, held since 2009 to commemorate Article 31 of the Constitution, which grants freedom of assembly, saw bans and crackdowns under Luzhkov, which prompted criticism from rights activists and Western politicians.
Federal authorities used Luzhkov's dismissal as a "pretext" to allow rallies on Triumfalnaya Ploshchad because they "provoked unnecessary madness in the West," Minchenko said.
The Day of Wrath on Saturday will not be limited to city issues, as participants also plan to demand free elections, lower utilities payments, crackdowns on employers who hire illegal migrants, aid to defrauded home buyers and an end to deforestation in the Moscow region town of Khimki because of a construction project.
Participants are asked to come dressed in black and carry “black marks” — any black items that can be presented to authorities as a sign of distrust of their policies, Left Front said on its web site.
The organizers have attempted to make Days of Wrath a monthly event so far, but said recently that they may switch to a quarterly schedule.