Obama vows to get tough with North Korea: President Barack Obama vowed Tuesday to take "firm action" with US allies against North Korea and South Korea accelerated a planned upgrade to its offensive missiles after Pyongyang's third nuclear test.
China, North Korea's trade and financial lifeline, signed up to a UN Security Council declaration accusing the communist state of standing in "grave violation" of UN resolutions amid global condemnation of Tuesday's blast.
The Council highlighted its threat made last month -- after North Korea breached UN resolutions by firing a long-range rocket -- to take "significant action" if Pyongyang went ahead with the nuclear test.
