"Given the reality where Korean Peninsula is in the state resembling war, the authorities’ actions [on deploying THAAD] are reasonable," Ban said, as quoted by the Yonhap news agency.
China and Russia have repeatedly showed their objection to the deployment of THAAD, arguing that their real aim was to deter the strategic weapon systems not only in the Korean peninsula’s North, but primarily in China's hinterlands and Russia's Far East regions.
Ban, whose second 5-year-term as the UN secretary-general expired at the end of 2016, is considered a possible presidential candidate in the wake of the political scandal around South Korean President Park Geun-hye.
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