The UN Security Council has strongly condemned North Korea's latest reported nuclear test.
The Security Council held emergency consultations on January 6 after Pyongyang announced it had carried out a "successful" underground hydrogen-bomb test.
The 15-member council described the reported test as a "clear violation" of council resolutions, adding that "therefore a clear threat to international peace and security continues to exist."
It also said it would "begin to work immediately" on a resolution to impose "further significant measures" against North Korea given the "gravity of this violation."
If confirmed, it would be North Korea's fourth nuclear test since 2006, but the White House said initial analysis was "inconsistent" with claims of a successful hydrogen-bomb test.
"Nothing occurred in the last 24 hours that has changed our assessment of North Korean nuclear capabilities," spokesman Josh Earnest said.