Warning North Korea against taking actions that will lead to the destruction of its people, US Secretary of State Jim Mattis on Wednesday asked Pyongyang to stand down pursuit of nuclear weapons.
"North Korea must choose to stop isolating itself and stand down its pursuit of nuclear weapons," Mattis said, urging Pyongyang to "cease any consideration of actions that will lead to the end of the regime and destruction of its people," Xinhua reported.
The US defence chief also warned that Pyongyang actions "will continue to be grossly overmatched by ours and would lose any arms race or conflict it initiates."
On Tuesday, US President Donald Trump issued a warning to Pyongyang that appeared to threaten a nuclear war with the Asian country.
"North Korea best not make any more threats to the US. They will be met with fire and fury like the world has never seen," Trump said at his golf resort in New Jersey.
In response, Pyongyang warned of preemptive strikes against the US military base of Guam in the Pacific.
US Secretary of State Rex Tillerson on Wednesday played down the threat from Pyongyang, telling Americans to "sleep well at night".
"Nothing that I have seen and nothing that I know of would indicate that the situation has dramatically changed in the last 24 hours," Tillerson told reporters.
"I think Americans should sleep well at night, have no concerns about this particular rhetoric over the last few days," Tillerson added.