Russia has summoned South Korea's ambassador to hand him a note of protest against Seoul's sanctions against Russian individuals and legal entities, reports "Reuters".
South Korea has imposed punitive measures against two Russian ships it says were carrying military cargo to North Korea.
On Tuesday, Seoul said it had also sanctioned two Russian organizations, as well as two Russian citizens, linked to Pyongyang's nuclear and missile programs.
Russian Foreign Ministry spokeswoman Maria Zakharova said yesterday that Russia considers South Korea's decision a hostile move and will respond in a timely manner.