North Korea says US approval for South Korea's nuclear submarine increases regional instability ↧ ↧ North Korea says US approval for South Korea's nuclear submarine in... North Korea's foreign ministry said ‌in a statement published by state media KCNA that the United States' ​approval for South Korea's building ​its first nuclear submarine is "a ⁠dangerous development" that added new ​instability to the political and military ​environment of the Asia-Pacific region.