The U.N. Security Council convened an emergency meeting Monday afternoon over North Korea's proclaimed second nuclear test.
The meeting between the council's five permanent members -- the United States, Britain, France, China and Russia -- and the 10 nonpermanent members began shortly after 4 p.m.
Earlier Monday Japanese Ambassador to the United Nations Yukio Takasu proposed that Russia, which currently holds the rotating monthly presidency of the Security Council, convene an urgent meeting to discuss North Korea's nuclear test.
The five permanent members of the U.S. Security Council plus Japan and South Korea met shortly before the council's urgent meeting apparently to discuss what action the Security Council should take following Pyongyang's claimed nuclear test earlier Monday.
Japan and the United States are expected to seek a Security Council resolution with the aim of imposing fresh sanctions on North Korea, while China and Russia are apparently cautious about such a move as it could hamper efforts to resume the stalled six-party talks on denuclearizing North Korea.
The six-party talks involve the two Koreas, China, Japan, Russia and the United States.
In Hanoi earlier Monday, Japanese Foreign Minister Hirofumi Nakasone met with his Chinese counterpart Yang Jiechi and sought Beijing's support for Tokyo's push to produce a U.N. Security Council resolution in response to the North Korean action.
But Yang was non-committal, telling Nakasone simply that China is seriously listening to Japan's position and wants to continue talks with Japan.
Japanese Prime Minister Taro Aso claimed that North Korea's action constitutes "a grave challenge" to the Nuclear Non-Proliferation Treaty and "a clear violation" of UNSC Resolution 1718, which bans any ballistic missile and nuclear activity by Pyongyang.
Japan's hope for the Security Council adopting a resolution following Pyongyang's rocket launch on April 5 was dashed mainly in the face of opposition from veto-wielding Security Council members China and Russia.
The Security Council instead adopted on April 13 a nonbinding presidential statement on the rocket launch that Japan and many countries believe was a disguised test-firing of a long-range ballistic missile. North Korea claims that the launch put a satellite into orbit.
After Pyongyang conducted its first nuclear test in October 2006, the Security Council unanimously adopted a resolution expressing "the gravest concern" and calling for all U.N. members to halt trade in weapons and luxury goods with the country.