BEIJING -- China on Monday warned against the deployment of an advanced US missile defense system in the Republic of Korea (ROK), saying China's security interests should not be undermined.

There were media reports that the Lotte Group board of directors met on Monday to approve a land swap deal between the military and Lotte -- a move to facilitate the deployment of the US Terminal High-Altitude Area Defense (THAAD).

The THAAD deployment initiated by the United States and the ROK seriously undermines regional strategic balance and the strategic security interests of regional countries including China, and is not favorable to safeguarding peace and stability in the Korean Peninsula, Chinese Foreign Ministry spokesperson Geng Shuang said at a regular news briefing.

"China has stressed time and again that it understands the reasonable security concerns of certain parties, but one country's security should not come at the expense of another," Geng said.

China regrets the persistent ignoring of its concerns over security interests, the spokesperson said. "China expresses firm opposition and strong dissatisfaction," he said.

China will take necessary measures to safeguard its security interests, and the U.S. and the ROK will have to bear all the resulting consequences, the spokesperson said.