Initial Analysis indicates that the nuclear test conducted by the Democratic People's Republic of Korea (DPRK) is "not consistent" with a hydrogen bomb, the White House said Wednesday.
At a regular briefing, White House spokesman Josh Earnest said nothing occurred in the last 24 hours has changed the U.S. assessment of the DPRK's technical and military capabilities.
The DPRK announced Wednesday that it has successfully carried out its first hydrogen bomb test.
Earnest said intelligence agencies are continuing to gather evidence to determine the nature of the test.
Any nuclear test conducted by the DPRK is "provocative and a flagrant violation of United Nations Security Council resolutions," Earnest said.
"We want the North Koreans (DPRK) to end their provocative acts both in the form of missile tests and nuclear tests, to commit to de-nuclearization and to demonstrate a commitment to pursuing peace and stability on the Korean Peninsula," Earnest said.
The spokesman also reiterated the "rock-solid" commitment of the United States to the safety and security of South Korea and Japan.
On Wednesday, U.S. Defense Secretary Ash Carter and his South Korean counterpart Han Min-koo spoke by phone to discuss potential responses by the two countries to the apparent nuclear test conducted by the DPRK, Pentagon spokesman Peter Cook said.
Cook said that the two leaders "agreed that any such test would be an unacceptable and irresponsible provocation and is both a flagrant violation of international law and a threat to the peace and stability of the Korean Peninsula and the entire Asia-Pacific region."
The two leaders agreed that the DPRK's provocations should have consequences, he said.
Also Wednesday, the top Democrat on the U.S. Senate Foreign Relations Committee called on the U.S. to respond "resolutely" to the DPRK's nuclear test.
"Today's reported nuclear test by North Korea (DPRK) is yet another indication of North Korea's (DPRK's) determination to continue to defy the international community and the threat it poses to regional peace and stability," said Senator Ben Cardin.
Cardin said he will work with others in the Senate on legislation to impose additional sanctions on the DPRK and also urged the United Nations Security Council to impose additional sanctions.
