Lyudmila Alekseyeva, head of Moscow's Helsinki Group and an organizer of the Strategy 31 protests, told RFE/RL that up to 1,500 people were expected to take part in the protest due to be held on Moscow's Triumph Square on January 31.
Strategy 31 is a campaign in support of freedom of assembly -- which is guaranteed by Article 31 of the Russian Constitution -- by holding demonstrations on the last day of the months that have 31 days.
The campaign was launched in 2009 by Eduard Limonov, a leader of the Other Russia opposition coalition. Other opposition groups and rights activists later joined.
Limonov and Alekseyeva split in October 2010 after the latter agreed to the authorities' request to limit the number of demonstrators. Limonov accused her of collaborating with Moscow officials.
Alekseyeva says she asked Limonov to join the action on an equal footing. Limonov announced earlier that he planned to hold a separate Strategy 31 gathering with his supporters on January 31.
Alekseyeva and Limonov held separate gatherings on December 31. Police detained 68 activists, including Limonov and prominent opposition figures Boris Nemtsov and Ilya Yashin, all of whom were given up to 15 days in jail.
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