North Korea issues nuclear threat against U.S.

North Korea warns "the moment of explosion is approaching fast." The country's army saying Wednesday it has final approval to launch "merciless" strikes against the U.S.

A warning posted by North Korea's state-run news agency reads:

"We formally inform the White House and Pentagon that the ever-escalating U.S. hostile policy toward the DPRK and its reckless nuclear threat will be smashed by the strong will of all the united service personnel and people and cutting-edge smaller, lighter and diversified nuclear strike means of the DPRK and that the merciless operation of its revolutionary armed forces in this regard has been finally examined and ratified," it said. "The U.S. had better ponder over the prevailing grave situation."

N. Korea threatens "merciless" strikes

OutFront tonight: CNN Contributor Ari Fleischer - White House Press Secretary under President George W. Bush and Gordon Chang, author of "Nuclear Showdown: North Korea Takes on the World."