"Here I am greeting people who believe, who believe in the better, who know that the bad is not forever. That happy endings exist not only in Hollywood movies, that progress wins," said Navalny, Ukraine Today reported.
Leading the demonstrations alongside Navalny was Illya Yashin.
Yashin is a Russian oppositionist and colleague of Boris Nemtsov, the government critic who was gunned down in Februrary of this year just ahead of publication of his investigative report into Russia's military aggression in Donbas.
A Reuters witness said there were some 3,000 protesters.
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