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SEOUL: The North Korean army said it had final approval to launch "merciless" military strikes on the United States, involving the possible use of "cutting-edge" nuclear weapons.
North Korea a 'real and clear danger'
North Korea represents 'a real and clear danger' to the U.S. and its Asian allies, says US Secretary of Defense Chuck Hagel.
In a statement published by the official KCNA news agency, the general staff of the Korean People's Army said it was formally informing Washington that US threats would be "smashed by . . . cutting-edge smaller, lighter and diversified nuclear strike means".
"The merciless operation of [our] revolutionary armed forces in this regard has been finally examined and ratified."
US Defence Secretary Chuck Hagel said North Korea's threats and recent actions represented a "real and clear danger" to the United States as well as its allies South Korea and Japan.
"They have nuclear capacity now, they have missile delivery capacity now," Hagel said after giving a major strategy speech at the National Defense University in Washington, calling Pyongyang's "bellicose dangerous rhetoric" problematic.
"We take those threats seriously, we have to take those threats seriously," he added.
"We are doing everything we can, working with the Chinese and others to defuse that situation on the peninsula.
"I hope the North will ratchet its very dangerous rhetoric down."
On Wednesday North Korea blocked access to the key Kaesong joint industrial zone with South Korea, the only surviving example of inter-Korean co-operation and a crucial source of hard currency for Pyongyang.
The move represented a sharp escalation of the military crisis. Tensions have been soaring on the Korean peninsula since the North launched a long-range rocket in December and conducted its third nuclear test in February.
In a rare show of force in the region, Washington has deployed nuclear-capable US B-52s, B-2 stealth bombers and two US destroyers to South Korean air and sea space.
We take those threats seriously, we have to take those threats seriously.US Defence Secretary Chuck Hagel
"We've been trying to work with the North Koreans to try to persuade them it's not in their interest, and certainly not in the Korean peninsula interest . . . to pursue nuclear weapons," Mr Hagel said.
"There is a pathway that is responsible, for the North to get on the path to peace, working with their neighbours . . . but they've got to be a responsible member of the world community."