Controversy resurfaced in South Korea over the deployment of an advanced US missile defense system called Terminal High Altitude-Area Defense (THAAD) amid lingering concerns about its effectiveness on the Korean peninsula and conflicts with neighboring countries.

The rekindled controversy came as some US media reported last week that the United States would talk with South Korea about the THAAD deployment on its ally's soil during the bilateral defense ministers' talks on the sidelines of the Asia Security Summit (the Shangri-La Dialogue) held last weekend in Singapore.

Seoul's defense ministry almost immediately responded to the media reports on Friday, denying the THAAD discussion which South Korea's Yonhap news agency described as an unusually swift response in consideration of past cases.

When one Japan-based TV reported on Friday that Seoul and Washington had agreed to deploy the US missile defense system in South Korea's southern city of Daegu sometime in 2017, Seoul's defense ministry spokesman made an almost immediate response in Singapore to say that no decision had been made yet.

Reversing the earlier cautious mode, Minister Han said on Saturday that South Korea has a clear will to deploy the THAAD on the peninsula, stressing its military effectiveness to defend his country from the Democratic People's Republic of Korea (DPRK)'s nuclear and missile threats.

Han said in an interview with CNN on Monday that the THAAD deployment would bring military benefits to South Korea as it strengthens the country's missile defense capability, while Yonhap cited multiple government sources as saying that multiple candidate areas for the deployment had been under detailed discussions between Seoul and Washington.

South Korea announced the start of discussions on the THAAD deployment on its soil following the DPRK's fourth nuclear test in January and the launch of a long-range rocket, which was condemned as a disguised test of ballistic missile technology, in February.

The deployment has been widely believed to escalate tensions and arms race in Northeast Asia as its radar can locate missiles far beyond the DPRK territory. The X-band radar can allegedly spot missiles as far as 2,000 km with forward-based mode and 600 km with terminal mode. As the two have the same hardware, the terminal mode, which South Korea plans to adopt, can be transformed into the radar with a much longer detectable range.

China and Russia have opposed to it as the US missile defense system far exceeds South Korea's actual defense needs and would directly threaten the strategic security of the two countries. Beijing and Moscow have called for Seoul and Washington to respect their stances and legitimate concerns.

Military effectiveness of the THAAD operation in South Korea has been in doubt as the US missile defense system is designed to track and destroy missiles at a high altitude of 40-150 km. Pyongyang would not use longer-range missiles in times of military conflicts with Seoul as hundreds of DPRK missiles targeting South Korea fly at a much lower range of less than 20 km.

The main opposition Minjoo Party reiterated its negative stance on the THAAD deployment, saying that the majority even in the United States didn't believe its defense capability was proven. Rep. Woo Sang-ho, the party's floor leader, said during a party meeting on Tuesday that worries remained among the general public about why the country should spend massive fiscal coffers on the unproven weapon.

Citing oppositions from China and Russia, Woo urged the government to think again about the oppositions as South Korea needs cooperation from China and Russia to denuclearize the Korean peninsula and secure peace and stability in Northeast Asia.

Civic groups also expressed oppositions. The People's Solidarity for Participatory Democracy, an influential liberalistic civic group, said in a statement on Tuesday that South Korea made the deployment as a fait accompli, which brought natural oppositions from China, a necessary partner in resolving the DPRK's nuclear issue.

Calling it a self-destructive misstep, the statement said that the THAAD deployment, irrelevant to South Korea's national defense, would provide no help in resolving the DPRK's nuclear crisis and speed up tensions and arms race in Northeast Asia.