he Security Council of the UN will meet in emergency Tuesday 9:00 (1400 GMT) to discuss how to respond to North Korea's nuclear test, condemned by the UN Secretary-General Ban Ki-moon as "profoundly destabilizing".
"This is a clear and serious violation of the resolutions of the Security Council," he said according to his spokesman Martin Nesirky.
Ban Ki-moon believes that the Security Council "remain united and take appropriate measures," he said.
London called Monday morning to a "strong response" of the Security Council of the UN, while U.S. Presidentcalls for action "fast" and "credible" international community.
North Korea conducted a nuclear test despite a "strong warning" of its ally China, said a UN diplomat. "The Chinese have launched the North Koreans a strong warning asking them not to perform this test when it became obvious that it was imminent," said the diplomat on condition of anonymity.
"What the North Koreans have is a real challenge to the Chinese," he said. Beijing, Moscow and Washington have worked together for a few days and "they will quickly agree on the fact that firm action is required," he added.
The Security Council is chaired in February by South Korea. The South Korean ambassador to the UN warned a few days ago that the Council would take action "very strong" in response to a third nuclear test Pyongyang (behind 2006 and 2009).
The Council decided in January to expand sanctions against the North Korean regime following the firing of a rocket North Korea in December.
Several UN resolutions prohibit North Korea nuclear or ballistic activity. Its rocket attacks and nuclear testing have earned Pyongyang a series of sanctions since 2006, including the freezing of assets belonging to North Korean companies or travel bans for regime officials.