South Korea's presidential office has said the ongoing deployment of the controversial US THAAD missile system should be suspended, accusing the defense ministry of trying to keep the planned introduction of further THAAD launchers under wraps, according to the national Yonhap News Agency.

Also ordering an environmental impact assessment into the system, a senior official told reporters on Wednesday, "We are not saying the two launchers and other equipment that has already been deployed should be withdrawn. But those that have yet to be deployed will have to wait."

A THAAD interceptor (R) in Seongju, South Korea. /VCG Photo‍

The remarks came after new South Korean President Moon Jae-in ordered a probe into the unreported deployment of four more mobile launchers of the missile shield into the country.

The investigation found that the head of the defense ministry's national defense policy office ordered officials to omit details of the deployment of four more THAAD launchers from a document submitted to the presidential Blue House.

The presidential office ordered the defense ministry to conduct a full environmental impact assessment, which could take up to a year, Yonhap cited the unnamed senior official as saying.

So far, two out of six THAAD launchers have been deployed. The presidential office said the other four will have to wait until the end of the study on their environmental impact.

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