Russia submitted a formal protest to Washington on Monday after the US Embassy in Moscow shared posts in support of demonstrations for the release of opposition politician Alexey Navalny.
Speaking to a Russian TV network, Russian Foreign Ministry Spokeswoman Maria Zakharova said Moscow viewed these posts as "direct interference in our country’s domestic affairs."
"Russia strongly protested against the US embassy's social media posts," Zakharova said, claiming that some US outlets spread "fake news" that Russia has taken note of.
Tens of thousands gathered in Russia on Saturday to protest Navalny's detention and demanding his immediate release. Many of the opposition figure's supporters were detained amid harsh police measures on the demonstrations.
The US Embassy had posted the date and places of the protests on social media.
Navalny, 44, who received treatment in Germany after alleged poisoning, was arrested in the Russian capital upon his return on Jan. 17. Russian authorities said he had violated probation terms from a suspended sentence on a 2014 money laundering offense, which Navalny says is "politically motivated."
Less than 25 hours after his return, Moscow's Khimki Court ruled that Navalny would remain in custody on 30-day pre-trial detention.
He is now behind bars in Moscow's infamous Matrosskaya Tishina jail.