SALEKHARD, July 23. /TASS/. South Korea and Japan undermine their own security by endorsing the US missile defense system’s deployment to their territory, while Russia and China have to take retaliatory measures, Russian Ambassador to China Andrei Denisov told reporters on Monday.

Russia suspects US may have full access to missile defense systems in Japan, Lavrov says

"Those who house such facilities on their territory, which our Chinese partners and we think pose a threat to our security, essentially put their security in jeopardy as we have to take some retaliatory measures, and this is absolutely obvious," the ambassador said.

In December 2017, Japan’s government made a decision to expand the country’s missile defense shield with two US-made Aegis Ashore missile defense systems, which are expected to be deployed to the north and southwest of the country’s main Island of Honshu tentatively in 2023 to help ensure security from possible ballistic and cruise missile attacks. These systems will cost Japan about 100 bln yen ($897 mln) each.

Russia and China have been opposing the deployment of US missile defenses to Japan, emphasizing that it would negatively affect the regional balance of power.

In June 2016, South Korea’s government announced that it backs the deployment of the US Terminal High Altitude Area Defense (THAAD) missile defense system. The ground-based system is designed to shoot down ballistic missiles in their terminal phase of flight and while approaching the target.

The pretext for deploying THAAD on the Korean Peninsula on a permanent basis was the need to counter North Korea’s missile and nuclear threat.