Kremlin critic Alexei Navalny was freed on Friday pending an appeal, a day after being sentenced to five years in prison for embezzlement.
The court said being in custody would strip him of his right to stand in elections for the mayoralty of Moscow in September.
Navalny's supporters said the decision to convict him was political.
A Kremlin spokesman has warned his supporters against trying to hold any more marches without official approval.
They had staged a number of unsanctioned rallies and must not break the law, he said.
On Thursday, Navalny was found guilty of heading a group that embezzled timber worth 16 million roubles ($US500,000) from the Kirovles state timber company while working as an adviser to Kirov governor Nikita Belykh.
He was sentenced to five years in prison. But on Friday, the Kirov regional court granted him bail.
In an unexpected move, the BBC reports prosecutors also pushed for him to remain free, with travel restrictions, pending his appeal.
The elections in Moscow are on 8 September.