Updated

President Vladimir Putin signaled his support Wednesday for a controversial bill now working its way through Russia's parliament that would increase fines 200-fold for those taking part in unsanctioned protests.

The bill received preliminary approval Tuesday in the elected lower house, where the Kremlin's United Russia party holds a majority. All three of the other parties voted against it.

Observers' reports of widespread fraud to boost results for United Russia in December's parliamentary election set off mass street protests that were unprecedented in post-Soviet Russia. The protests have evolved into regular rallies and, in Moscow, continuous Occupy-style demonstrations decrying Putin's subsequent election to a third presidential term.

Opposition lawmakers have warned that the new fines will only fuel broad outrage and destabilize Russia by depriving the public of a legal way to voice grievances. The bill raises fines for joining unsanctioned rallies from the current maximum of 5,000 rubles ($160) to 1,000,000 rubles ($32,250).

Yet Putin defended the bill Wednesday, describing it as "strengthening democracy."

"We must shield our people from radical actions," he said in remarks broadcast from a meeting with United Russia members. "The society and the government have a right to protect themselves from this."

A protest rally a day before Putin's May 7 inauguration spilled into violence between protesters and the police. Authorities blamed the opposition, while opposition leaders said the violence was incited by unknown provocateurs.

Putin also scolded the chairman of the presidential council for the development of civil society and human rights for publicly criticizing the bill.

"You are a presidential adviser and can address the president directly," Putin told Mikhail Fedotov, who had been invited to attend the party meeting.

Fedotov quickly backed away from his earlier criticism, telling Putin he had taken another look at the bill approved by parliament and saw that his concerns had been addressed.

The bill has two more required votes in June, with United Russia aiming to get the increased fines passed into law ahead of a June 12 holiday, when opposition leaders have called for the next large protest.

Opposition leaders Sergei Udaltsov and Alexei Navalny were due to be released Thursday after spending 15 days in jail. Both men were arrested during the protests that accompanied Putin's inauguration.