Pentagon chief Jim Mattis on Wednesday warned North Korea to stop pursuing nuclear weapons and stop considering actions that would lead to the "destruction of its people."

"The DPRK (Democratic People's Republic of Korea) must choose to stop isolating itself and stand down its pursuit of nuclear weapons," Mattis said in a statement. 

"The DPRK should cease any consideration of actions that would lead to the end of its regime and the destruction of its people."

He added that: "The DPRK regime's actions will continue to be grossly overmatched by ours and would lose any arms race or conflict it initiates."