Beijing, April 26 (IANS): Hours after the deployment of a US advanced defence shield went into full swing in South Korea, Beijing on Wednesday strongly urged Seoul and Washington to pull back the equipment, warning that the installation would further heighten tensions in the region.

Six trailers carrying the high-profile X-band radar of the Terminal High Altitude Area Defence (THAAD) system, mobile launchers and other elements were seen entering the deployment site in the south-eastern county of Seongju, North Gyeongsang province, starting around midnight.

The radar and launchers, key elements of the missile interception system, are likely to go into test operation in the near future, Yonhap news agency reported. 

"We have already expressed our grave concerns to the South Korean and US governments," China's Foreign Ministry spokesman Geng Shuang said in a press briefing after being asked China's stance on the deployment. 

"The deployment of THAAD in South Korea would destroy the strategic balance and incite a further rise in the tensions," he said.

"The Chinese side strongly urges the US and South Korea to cancel the deployment and withdraw the equipment," the spokesman noted.

The deployment runs counter to the principle of resolving the Korean Peninsula issue through dialogue and negotiation as well as the goal of denuclearising the peninsula, the spokesman added.

Geng Shuang then reiterated that bringing THAAD to the peninsula "gravely impairs" the strategic security interests of China, pledging to take action in response.

"China will not fail to sternly take action necessary to safeguard its interests," he said.