Beijing reiterated that China would "resolutely" take necessary actions to protect its security interests in response to US deployment of the Terminal High Altitude Area Defense system in the Republic of Korea.

Foreign Ministry spokeswoman Hua Chunying made the remark Thursday in response to Michael Flynn, US president-elect Donald Trump's designated national security adviser, calling the decision to deploy THAAD an "appropriate move".

"China has repeatedly expressed its serious concerns and clear opposition," Hua said. "The THAAD deployment by the US in the ROK severely undermines the regional strategic balance and the strategic and security interests of relevant regional countries including China.

"It will not help preserve the peace and stability of the Korean Peninsula. We hope that relevant countries can take our legitimate concerns seriously and halt the deployment."

This was the first time that a senior adviser to Trump offered clear backing for THAAD. It suggests that Trump, who repeatedly hinted in the election campaign at the possibility of the US reducing its military presence overseas, would continue to pursue deployment of the THAAD antimissile system in the ROK, according to the ROK's Dong-A Ilbo newspaper.

Flynn, speaking to a delegation from Seoul in Washington, said, "The Seoul-Washington alliance remains strong and firm," according to media reports. He also called for closer collaboration with Seoul to deal with nuclear and missile issues from Pyongyang, which THAAD was designed to deter.

Shi Yongming, an Asia-Pacific studies researcher at the China Institute of International Relations, said THAAD support from a Trump senior adviser is meant to strengthen the trilateral intelligence alliance between US, ROK and Japan, and "build a NATO-like organization in Asia."

"The US can use THAAD as a ploy to install powerful radar that can detect missile activities in China and Russia," said Shi. With the ROK and Japan signing an intelligence sharing pact last month, the US might put forward its own intelligence sharing pact and use THAAD to give itself an edge in negotiations, Shi said.

Teng Jianqun, research director at China Arms Control and Disarmament Association, said the goal is to use THAAD in the ROK to contain China.

Last week, ROK leadership contender Moon Jae-in suggested the deployment should wait, but acting President Hwang Kyo-ahn on Wednesday called for immediate deployment of THAAD to deter the Democratic People's Republic of Korea, according to Yonhap news.

In the final analysis, it will be the ROK population that will decide the fate of THAAD, which remains uncertain given the country's internal turmoil, Teng said.

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