US President Barack Obama today warned North Korea it risks deepening its isolation in the international community if it proceeds with a planned long-range rocket launch.

North Korea's quest for nuclear weapons could spawn a destabilising arms race in Asia that would threaten world security, South Korea's president warned today.

A South Korean news agency has said that North Korea test-fired a short-range missile, a report that came shortly after the communist nation declared that it successfully conducted a nuclear test today.