Russia is asking NATO and a European security organization to explain how they intend to comply with their commitment not to strengthen security at the expense of others.
Russian Foreign Minister Sergey Lavrov said on Sunday that Russia is sending the official requests to NATO and the Organization for Security and Co-operation in Europe.
He argued that if NATO grants membership to Ukraine, it will contradict the alliance's commitment.
Lavrov reiterated calls for NATO to guarantee in a legal document that the alliance will not expand. He stressed that would ensure security on the entire European continent, with full and equal regard to Russia's legitimate interests.
Meanwhile, Russia's Security Council Secretary Nikolai Patrushev dismissed US warnings that Moscow may invade Ukraine in February.
Patrushev told reporters on Sunday that Russia does not want war.