Election Commission official Dmitry Krasnyansky was quoted by Interfax news agency as saying nearly 12 percent of the signatures submitted in support of Yabloko's candidates have been declared invalid by authorities -- more than the maximum 10 percent allowed.
Yabloko official Maksim Reznik told Reuters the party believes it was barred because it is in opposition to the current St. Petersburg authorities.
He told a news conference the party will appeal the decision on January 30 or 31.
In Moscow, about 100 protesters gathered outside the Kremlin to denounce the ban.
Democracy In Russia
Demonstrators in Moscow carry a coffin with a television in it to protest government control over broadcasting (TASS file photo)
DO RUSSIANS LIKE THEIR GOVERNMENT? During a briefing at RFE/RL's Washington office on November 15, Richard Rose, director of the Center for the Study of Public Policy at the University of Aberdeen, discussed the results of 14 surveys he has conducted since 1992 on Russian public opinion about democracy and the country's development. He discussed the implications of these opinions for relations with the West and for Russia's 2008 presidential election.
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