The top military officers of South Korea and the United States held talks on bilateral security issues on Friday amid swirling speculation they could discuss the deployment of an advanced U.S. missile-defense system here.

Adm. Choi Yun-hee, South Korea's Joint Chiefs of Staff chairman, and his U.S. counterpart Gen. Martin Dempsey began their 90-minute meeting in Seoul "to deal with a wide range of issues, including how to deal with North Korea's evolving nuclear and missile threats and their preparedness," Seoul's JCS said.

While the JCS and the defense ministry here have stressed that the Terminal High-Altitude Area Defense issue would not be on the agenda, observers said the top military officers could touch upon the issue "at least in an unofficial fashion."

The possible deployment of the missile-defense system has been a hot-button issue facing South Korea amid strong opposition from China, Seoul's largest trading partner.

The U.S. hopes to deploy THAAD in South Korea to counter ballistic missile threats from North Korea and guarantee the safety of about 28,000 U.S. troops stationed here and their families, saying it is a purely defensive system.

But China has repeatedly voiced its opposition to the possible deployment of a THAAD battery on South Korean soil, suspecting it is part of U.S. attempts to contain an increasingly assertive China.

Heading for Japan, the first leg of his Asian tour, Dempsey said Tuesday that building an integrated air and missile-defense system will be a key topic of discussions when he meets with South Korean officials.

Noting that Washington is making progress on building the integrated defense umbrella, the general said Seoul and Tokyo have "made some commitments in procurements on their side to make us more interoperable."

As an integral part of the U.S.-led air defense system for the region, the THAAD is designed to intercept short-, medium- and intermediate-range ballistic missiles at high altitudes in their terminal phase. 

Dempsey arrived here on Thursday for a three-day trip. It is considered a return visit before he leaves office at the end of September, according to the JCS, noting that Choi traveled to the U.S. in July. (Yonhap)