Members of Russia's Duma voted on Friday to pass a bill that prohibits Virtual Private Networks (VPNs) and other internet proxy services that allow users to make their online activity untraceable.

The law instructs Russia's telecommunications watchdog to compile a list of anonymizer services and prohibit any that fail to respect the bans issued in Russia on certain websites.

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Critics said the move was the latest in a long-running effort by the Kremlin to tighten control of the internet, which has led to many Russians to use VPNs to access blocked online content by routing connections through servers outside the country.

Too restrictive

Several internet-based groups in Russia have condemned the new law as too vaguely formulated and too restrictive.

But the government has cited security concerns for the move, saying that VPNs make it hard to identify users who are sharing extremist content.

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The law also obliges anyone using an online message service to identify themselves with a telephone number.

In June, Russian officials threatened to ban the Telegram messaging app after the FSB intelligence agency said those behind April's deadly Saint Petersburg metro bombing had used it.

Authorities also insist internet companies store privacy data on Russian servers, having blocked the business-focused social network LinkedIn because it violated the rule.

The bill still has to be approved at the upper chamber of parliament and signed by Russian President Vladimir Putin before it comes into effect.

mm/jm (AFP, AP, dpa)