[JURIST] The UN Security Council is set to meet [AP report] in emergency session to discuss possible courses of action after North Korea (DPRK) [JURIST news archive] exploded several test nuclear weapons underground Monday. North Korea's official Central News Agency [media website] reported that the tests were performed safely and no radiation leakage was detected. North Korea pulled out of the Nuclear Non-Proliferation Treaty [PDF text; IAEA backgrounder] in 2003 and international law regarding nuclear weapons is therefore largely inapplicable to the country. In a statement [text] made last week announcing its intent to conduct the nuclear test, North Korea said:

The US extreme threat of a nuclear war and sanctions and pressure compel the DPRK to conduct a nuclear test, an essential process for bolstering nuclear deterrent, as a corresponding measure for defence.

Secondly, the DPRK will never use nuclear weapons first but strictly prohibit any threat of nuclear weapons and nuclear transfer.