Vladimir Putin, Russia's president, has called the Internet a "CIA project" and warned Russians against making Google searches.

Speaking to a group of young journalists during a televised event on Thursday, Putin said the Internet was developed by the US as a "special project" by the Central Intelligence Agency.

When asked about Google, the Russian leader said the company's web traffic "goes through servers that are in the States", adding "everything is monitored there", the AFP news agency reported.

Shares in Russia's biggest search engine, Yandex, fell as Putin expressed concern about its overseas investors, reiterating his fear of foreign control of the Internet.

"We must fight determinedly for our own interests. This process is happening. And we will support it from the government side, of course" he said.

The Kremlin has been anxious to exert greater control over the Internet, which opposition activists, who are barred from national television, have used to promote their ideas and organise protests, the AP news agency reported.

Russia's parliament passed a law earlier this week requiring social media websites to keep their servers in Russia and save all information about their users for six months.

Another new law allowed the government to block blacklisted sites without a court order, and businessmen close to the Russian president now control the country's leading social media network, VKontakte.

Opposition leader Alexei Navalny had his popular blog blocked and a widely read news site that covered opposition causes sacked its long-term editor and changed its stance after a warning on extremism from the state watchdog.

Putin has frequently been scathing about the Internet, which he once described as "half pornography".