Human rights NGOs, including Amnesty International and Reporters Without Borders, have expressed concern over the amendments that label journalists, bloggers and internet users as "foreign agents".
Russian President Vladimir Putin signed a controversial law on Monday, allowing independent journalists and bloggers to be labelled as "foreign agents", a move that critics say will violate media freedom.
Russian legislation passed in 2012 already gave authorities the power to brand media organisations and NGO's as foreign agents, a term that has Soviet-era overtones.
The new law, which now extends to individuals, will come into effect immediately, according to a document published on the Russian government website.
Foreign agents, defined as involved in politics and receiving money from abroad, must register with the justice ministry, label publications with the tag and submit detailed paperwork or face fines.
Further restrictions on expression
Nine human rights NGOs, including Amnesty International and Reporters Without Borders, have expressed concern that the amendments may be aimed not only at journalists but also at bloggers and internet users who benefit from scholarships, funding or revenues from a relevant media outlet.
NGOs said in a joint statement last month the law was "a further step to restrict free and independent media" and "a strong tool to silence opposition voices".
Authors of the bill have said it is intended to "perfect" existing legislation on "foreign agents" that already covers NGOs and media organisations.
Russia says it wants the law as a tit-for-tat mechanism if its journalists are defined as foreign agents in the West.
Russia first passed legislation allowing media organisations to be slapped with the label in 2017 after Kremlin-funded RT television was declared a foreign agent in the US.
Russian opposition politician Alexi Navalny's organisation has been branded a foreign agent, as has US-financed media outlet Radio Liberty/Radio Free Europe and Voice of America.
The term foreign agent was used negatively during the Stalinist era in the 1970s and 1980s for opponents accused of being paid by the West.