Seoul: A key North Korean nuclear complex has been experiencing "modernization and expansion" throughout the year, as reported by a U.S. website that monitors the reclusive state.

According to Yonhap News Agency, "Commercial satellite imagery of North Korea's Yongbyon Nuclear Scientific Research Center from October and November 2025 shows continuation of modernization and expansion efforts throughout the site." The Yongbyon facility plays a critical role in the country's production of nuclear material for its weapons program, being the sole producer of plutonium and a significant source of enriched uranium.

In a separate development, the U.S. Forces Korea (USFK) clarified on Friday that its combined military drills with the South Korean military are "strictly defensive" in nature. This statement followed accusations from North Korea, which criticized the joint exercises as being aimed at deterring the North. The USFK's remarks came shortly after Pyongyang condemned a series of combined military drills between the allies, including the Silent Shark anti-submarine warfare drills and the recent U.S. forward deployment of F-16 fighter jets to Osan Air Base in South Korea.