Moscow's Court of Cassations No. 2 said on March 2 that it rejected a motion by Konstantin Kotov's lawyers and prosecutors to annul a four-year prison term handed to the activist, Radio Free Europe / Radio Liberty (RFE/RL).

His lawyers wanted the case against their client to be closed and the charge to be dropped, while prosecutors had asked the court to cut the prison term to one year.

The court also ruled that Kotov must be kept in pretrial detention until May 2.

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The 35-year-old computer programmer was detained on August 10 for taking part in a rally to demand that opposition and independent candidates be put on the ballot for the Moscow City Duma election that was held on September 8.

The barring of the would-be candidates sparked a wave of protests in Moscow and elsewhere in Russia last summer, some of which were violently suppressed by police as thousands were briefly detained, sparking international condemnation.

Kotov was one of several activists punished with prison following the protests in what has been dubbed the Moscow Case.

His conviction and sentencing on September 5 sparked a public outcry in Russia because of its severity.

On January 25, amid protests against Kotov's imprisonment, President Vladimir Putin ordered the Prosecutor-General's Office to review the legality of the sentencing.

Two days later, Russia's Constitutional Court ruled that the case must be reviewed.