Russia has threatened to block ads appearing on Google, following Google's move to de-rank posts from Kremlin-funded news outlets RT and Sputnik, which are accused of propaganda.

Google announced plans to "de-rank" Kremlin-funded RT and Sputnik in news search results.

Last weekend, Alphabet CEO Eric Schmidt, said that the search engine was preparing to de-rank posts related to Russian news outlets, which are accused of spreading misleading pro-Kremlin propaganda.

Russian media watchdog Roskomnadzor has demanded Google explain its reasoning behind the de-ranking plans.

"We are also concerned about the situation with information that's undesirable and dangerous for readers," Piotr Tolstoy, deputy chairman of the State Duma - the lower chamber of the Russian parliament - was quoted as saying by RIA Novosti. "We would like to talk to [Google] about how to defend Russian citizens from dangerous content. And if we can't come to terms, let's just block all their ads with a legislative decision."

Russia's media watchdog has already threatened to block Facebook in the country, accusing the social network of violating a data storage law requiring that Russian citizens' personal data be stored within Russia.

Last month, Twitter chimed in, banning all ads from RT and Sputnik.