The United States says that if North Korea goes ahead with its announced plan to conduct a nuclear test, it would pose a threat to peace and security in the Asia-Pacific region.
In a statement, the White House said the U.S. is "seriously concerned" about the possibility of a North Korean nuclear test and will work with Japan, South Korea and its other partners on the issue.
North Korea's foreign ministry said Tuesday the country will conduct a nuclear test to bolster its defenses against what it calls U.S. hostility. The official Korean Central News Agency said the nuclear test will take place "in the future," but did not specify a date.
Meanwhile, the U.N. Security Council was divided on a response to North Korea's announcement.
U.S. Ambassador John Bolton said he wants Security Council members to meet on Wednesday to formulate a long-term strategy over North Korea's nuclear ambitions. China said the issue would be better handled in the stalled six-nation talks with Pyongyang.
Australian Foreign Minister Alexander Downer said he will try Wednesday to meet with the North Korean ambassador to protest the planned nuclear test.
The Japanese and British governments said such a test would result in serious consequences. The European Union said today that the announcement is an "irresponsible and escalatory step" that increases tension and undermines regional stability.
South Korea said it has strengthened its security level and alert status as a result of the North Korean statement.
But the Russian foreign ministry cast doubts on the threat, saying North Korea has made similar claims before.