MOSCOW — Russia formally protested to the US embassy in Moscow on Monday over social media posts it said promoted anti-Kremlin demonstrations and accused US tech giants of interfering in its internal affairs.

On Saturday, tens of thousands rallied in support of jailed Kremlin critic Alexei Navalny.

Russia's deputy foreign minister held talks with the US ambassador to register dissatisfaction over the embassy's messages, ministry spokeswoman Maria Zakharova told state-run media.

During the meeting, she said, Sergei Ryabkov expressed "strong protest" over the US embassy "spreading posts supporting illegal rallies in a number of Russian cities on social networks and on their Internet platforms".

The meeting followed accusations by Kremlin spokesman Dmitry Peskov that the US embassy was interfering in Russia's domestic affairs after the embassy issued a "demonstration alert" to US citizens in the country.

A US embassy spokeswoman told AFP that it was "routine practice" for US embassies and consulates to issue safety messages to American citizens abroad.

Zakharova on Monday also said Russia would probe American IT companies over "interference" in the country's domestic affairs.

"We are doing serious work on how American Internet platforms were involved in the American side's interference in our internal affairs," she said.

Ahead of the rallies, Russia's media watchdog Roskomnadzor ordered several social media platforms, including YouTube and Instagram, to delete calls for demonstrations that were posted on their platforms.

More than 3,700 demonstrators were detained during the rallies, the OVD Info monitor reported, with several protesters injured in clashes with riot police.