Russia's Supreme Court has upheld a ruling barring opposition leader Alexei Navalny from running in the March presidential election.
The high court upheld the Central Election Commission's decision banning Navalny from running because of his conviction on criminal charges.
Navalny and his followers say those charges were politically motivated.
Navalny has called for demonstrations across Russia on January 28 to protest the country's upcoming presidential vote.
Polls say that incumbent President Vladimir Putin will likely win another six-year term when the election is held on March 18.
Navalny contends that Putin, who has spent the last 17 years as either president or prime minister, has been in power too long. The opposition leader says Putin's popularity is largely due to biased state media and an electoral system that excludes legitimate opponents.
Putin, a former KGB officer, is running as an independent, a decision some observers believe would enhance his image as a leader of a nation instead of a party political figure.
Allies have praised Putin for restoring national pride and enhancing Russia's position as a global leader with military interventions in Syria and Ukraine.