Ryabkov said this on the sidelines of the Valdai Discussion Club. His words are quoted by RIA Novosti.
He commented on the proposal of Congressman Lindsey Graham to shoot down Russian aircraft that approach American ones in international airspace.
In his opinion, such statements by US congressmen should be taken seriously, since they reflect the willingness to do everything to damage Russia in all spheres, including the military.
Ryabkov added that this is a reflection of the fact that people who make such statements either "have little idea of the realities of the nuclear age" or have completely forgotten that Russia is ready to defend itself from aggressive attacks by all means that it has at its disposal.
He also said that de facto Russia is in a state of open confrontation with the United States.