Joint naval exercises

A spokesman from South Korea's defense ministry confirmed that the three-day drill was underway in the Sea of Japan, near the port of Pohang. South Korean officials have stressed that the exercise was planned well before North Korea threatened to conduct a third nuclear test, many regard the show of military might as a tacit warning to Pyongyang.

Among the warships involved is the USS San Francisco, which is armed with Tomahawk cruise missiles, and the USS Shiloh (pictured above), which features guided missiles and rapid-fire cannons.

"The exercise includes at-sea operating training, detecting and tracking a submarine, anti-air and anti-ship live fire training and anti-missile training," a military official told South Korea's Yonhap news agency.

Pyongyang regards the joint exercise as a provocation – on Saturday state media characterized it as being in preparation for a pre-emptive strike on North Korea. Pyongyang has made similar complaints about previous US-South Korean naval exercises.

These maneuvers began a day after a reported speech by North Korean leader Kim Jong Un raised speculation that Pyongyang's planned nuclear test could be imminent.

In the speech to North Korea's Central Military Commission, Kim issued "important" guidelines on how to bolster the country's armed forces and safeguard the country's security, according to the official Korean Central News Agency.

The report followed a series of statements issued by Pyongyang over the past few days, in which it vowed to retaliate for the latest round of United Nations Security Council sanctions, which were tightened last month following a long-range rocket launch.

The United States, South Korea and their allies accuse North Korea of using the December launch as a pretext to test ballistic missile technology, something it was banned from doing under previously existing sanctions. Pyongyang claimed there was no military element to the launch, and that it was used to send satellites into orbit.

pfd/hc (AP, AFP)