US, South Korea begin naval exercises

The United States and South Korea have embarked on joint military exercises condemned as "warmongering" by North Korea. As Alastair Wanklyn reports from Tokyo, nations in the region remain braced for a nulcear test by North Korea.

The exercises include anti-aircraft and missile countermeasures involving United States naval vessels including a nuclear submarine armed with long-range missiles. The naval exercises are a reminder that the U.S. is obliged to defend its South Korean ally from attack.

North Korea has called the three days of manoeuvres "warmongering."

Separately, state media there this weekend reported the North Korean leader met commanders to discuss an unspecified pivot in military ability, taken to mean a new nuclear capability that would be proven by a new nuclear test, as threatened in recent days.

Officials in the south insist the exercises were planned before the North threatened to carry out that test, expected to come this month, around the time the South inaugurates a new president.

In Japan, diplomats have been pressing for significant new in the event North Korea again defies international demands. North Korea is already under wide-ranging sanctions. But now even North Korean ally China has threatened a cost. And South Korea plans to restrict cooperation with a free-trade zone in the north.

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