Russian is still studying the responses of the U.S. and NATO on the security guarantees and is preparing a comprehensive response, RIA News Agency reported on Tuesday, citing information from Russian Foreign Ministry sources.

Russian Foreign Minister Sergey Lavrov and his U.S. counterpart Antony Blinken will discuss Moscow's reaction to the U.S. solutions on Russia's proposals in the security sphere in a phone conversation on Tuesday, the Russian Foreign Ministry told TASS.

"The main subject is the reaction of the Russian side to the American solutions on Russia's proposals in the sphere of security guarantees. It is expected that following the phone conversation, Sergey Lavrov will comment on the situation in media outlets," the statement said, according to the report.