US to hold sea drill with South Korea in warning to North
Three-day exercise by US and South Korean navies featuring a nuclear submarine comes as Pyongyang apparently readies for atomic test

South Korea and the United States will hold a joint naval exercise beginning tomorrow involving a US nuclear submarine, in a move seen as a warning to North Korea ahead of its widely expected nuclear test.

Meanwhile North Korea accused the US of double standards and said it would face the "toughest retaliation" for criticising its rocket launch while supporting one by South Korea.
The UN Security Council has imposed new sanctions on Pyongyang for its launch, conducted last month.
Analysts say Pyongyang has resumed work for a third nuclear test a week after it threatened to conduct one in response to strengthened UN sanctions.
The North said the rocket launch was a scientific mission aimed at placing a satellite in orbit, but most of the world saw it as a disguised ballistic missile test.