Seoul has let Moscow and Beijing know in advance of the decision to start official negotiations with Washington on the deployment of the Terminal High Altitude Area Defense (THAAD) system on the South Korean territory, the government said in a statement on Sunday.

Earlier in the day, Yoo Jeh-seung, South Korean deputy minister for policy, said that South Korea and the United States had agreed to start talks on the deployment of the advanced US missile defense system.

“(We) have informed the Chinese and the Russian side [of the decision to start the negotiations] before the official Defense Ministry statement was issued,” the statement reads, as quoted by the Yonhap news agency.

The United States has raised the possibility of the deployment of a THAAD battery in East Asia in the past, a decision the Pentagon has said would be made through the trilateral Japan-South Korea-US security alliance talks.

China and Russia have expressed concern over the controversial defense system, arguing it could upset the regional balance and be used against Chinese interests.