The Russian authorities have told Google, Facebook, and Twitter that they face prosecution if they do not comply with the country's crackdown on free speech.

Under a new Russian law, the three US firms must register as "organizers of information distribution," and store all data on Russian users in data centers on Russian soil. The Vladimir Putin-led nation also reserves the right to remove any material posted by Russians that is deemed offensive, or that breaches Russian election regulations.

"If they do not comply with the requirements of Russian legislation, they would face administrative sanctions," Maxim Ksenzov, deputy head of the Russian Federal Service for Supervision of Communications, Information Technology, and Mass Media (Roscomnadzor) told newspaper Izvestia.

"These three resources need to decide on the placement of its data centers in Russia and the laws of the bloggers."

Ksenzov said social networks and blogging sites with more than 3,000 readers have already registered, and the California giants need to do the same – or face fines of up to 500,000 roubles ($12,762) and a ban on doing business with Russian consumers. Google, Facebook and Twitter are unlikely to care about a $13k fine, if it's a one-off penalty, but the ban would be a problem.

Civil rights campaigners warned in May that the new laws would be used to not only extend state control over domestic internet users, but would be applied to overseas firms as well. Now, it seems, the Putin government has started drawing battle lines, although negotiations are ongoing.

"We have informed all, and we will make them abide by the law, this or that way," Ksenzov said. "They are holding consultations with each other, and with Californian lawyers. We are also in consultations with them, but so far we are not pressing."

Neither Google, Facebook, nor Twitter had any comment to make at time of publication. ®