"We will continue our course firmly and consistently. Sanctions or their absence will have no impact on what we did and will do in our relations with Kiev, on what we suggest and what we keep in mind while promoting stabilization in the southeast and the launch of internal political process in Ukraine," the Russian diplomat said, adding that Russia should "be ready for everything" in its relations with the United States.

Underlying the US current policy is "the intention to build up pressure before the dynamics of situation in Ukraine changes," Ryabkov stated. The diplomat criticized the US political line that fails to correspond to reality. "I have grave doubts that Washington officials formulating policy toward Russia and Ukraine perceive the reality adequately," Ryabkov said, adding that he hopes such "political surrealism" will not dominate.

Ryabkov also noted that the US administration has managed to demolish "the efficient working mechanism" that Russia and the United States managed to set up in the recent past.

A new round of Western sanctions against Moscow over its alleged role in the Ukrainian crisis came into force on September 12. The sanctions complicate access to EU and US credit for a number of key Russian banks and oil and defense companies and ban the provision of technical and other assistance to Russian oil companies.