The United Nations has no immediate comment on news that North Korea has conducted its first nuclear weapons test, a spokeswoman said early on Monday.
"We have not received any information from the Security Council. We have no comment," said duty officer Fang Chen.
The communist state's official Korean Central News Agency (KCNA) earlier announced that North Korea conducted an underground nuclear test safely and successfully and there was no radiation leak.
The 15-member Security Council was expected to hold an emergency meeting on the North Korean test later on Monday.
Last Friday, it unanimously adopted a non-binding statement expressing "deep concern" over Pyongyang's plan to go ahead with a test and made it clear that such a move "would represent a clear threat to international peace and security."