Alexei Navalny, leader of the Russian Opposition Coordination Council, said the rallies, one in April and another in May, will be held under the banner "For Freedom!"
The group staged protests in advance of Putin's inauguration a year ago. A dozen people were arrested and charged with inciting violence and using violence against a police officer.
Navalny said Saturday promenades will be staged, with marchers bearing white ribbons, the group's symbol, RIA Novosti reported.
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