Andrey Smirnov / AFP - Getty Images

A police officer detains a protester wearing white ribbons, a symbol of the Russian opposition, outside Russia's lower house of parliament in Moscow on Tuesday.

MOSCOW - Russian lawmakers have voted through a controversial bill that dramatically increases fines for those accused of participating in unauthorized public protests, state news agency RIA Novosti reported Wednesday.

The Upper House of the Duma – the country’s parliament – approved the bill despite anger from opponents of President Vladimir Putin and his ruling United Russia party. 

It would boost fines from the current 5,000 rubles ($152) to 300,000 rubles ($9,225) for citizens participating in demonstrations at which public order or city rules are deemed to have been violated. Rally organizers could also face fines of up to 600,000 rubles ($18,454), RIA Novosti said. The bill requires Putin's signature to become law, but the president has already indicated he supports the measures.

Police detained about 20 activists protesting late Tuesday outside the Duma, Reuters reported.

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The bill was proposed in response to big public rallies against Putin's second term as president.

'Monstrous'
Critics say it is being fast-tracked through the Duma ahead of a planned mass protest in Moscow on June 12.

"This is a monstrous bill which will essentially ban people from protesting," Sergei Mitrokhin, an opposition leader whose Yabloko party has no seats in parliament, told Reuters outside the Duma.

Moments later, he was roughly detained with other activists, many wearing the white-ribbon symbol of the anti-Putin movement.

In a sign he would brook no Western criticism on human rights or democracy, Putin – a 59-year-old former KGB officer - defended tougher rules governing protests as being in line with European norms.

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However, some of the original proposals in the bill, such as fines for Internet users who spread the word about rallies, were dropped.

Opposition leaders and rights activists, including U.S.-based Human Rights Watch, say the law violates the 31st article of Russia's constitution on the right to free assembly.

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Gennady Gudkov, a lawmaker with the opposition Just Russia party, described the bill as "draconian", saying it reflected the Kremlin's "fear of people", according to a BBC report.

"It is the path toward civil war, it is the path towards massive repression and we all know how that ends: in blood, poverty and revolution," Gudkov added.

Reuters and msnbc.com's Alastair Jamieson contributed to this report.

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