SEOUL • As the United States and South Korea prepare for next week's joint naval exercise, North Korean officials yesterday renewed their threat to launch ballistic missiles near Guam, an American territory in the western Pacific.
The 10-day drill, which involves the aircraft carrier Ronald Reagan, is set to begin on Monday in waters east and west of South Korea.
The nuclear-powered submarine USS Michigan arrived at the South Korean port of Busan yesterday, and US and South Korean warplanes will also join the exercise, which takes place amid heightened tensions over North Korea's advancing nuclear missile programme.
Meanwhile, a researcher at the Institute for American Studies at the North Korean Foreign Ministry warned that the joint exercise, as well as a flight by two US bombers over South Korea on Tuesday, has compelled the North to "take military counteraction".
Mr Kim Kwang Hak did not elaborate but recalled Pyongyang's warning in August that it could launch missiles near Guam, home to the US airbase from which the bombers took off on Tuesday. North Korean leader Kim Jong Un has said he would watch the Americans before deciding when to launch an "enveloping fire" around Guam.
"We have already warned several times that we will take counteractions for self-defence, including a salvo of missiles into waters near the US territory of Guam," Mr Kim, the researcher, told the North's official Korean Central News Agency.
"The US military action hardens our determination that the US should be tamed with fire and lets us take our hand closer to the 'trigger' for taking the toughest countermeasure."
Separately, a small quake was detected early yesterday near the North's nuclear test site, South Korea's weather agency said, but unlike quakes associated with nuclear tests, it did not seem to be man-made. The shock was the latest in a string of at least three since Pyongyang's Sept 3 test, which caused a 6.3-magnitude earthquake.
The tremors and landslides near the nuclear test base likely mean the North's sixth and largest blast has destabilised the region, and the Punggye-ri nuclear site may not be used for much longer, experts said.
Commercial satellite images have found evidence of landslides near the site, raising fears of radioactive fallout if the North holds another nuclear test there.