North Korea says it has approval to use its 'cutting edge' nuclear weapons against the United States in a 'merciless' attack just hours after Chuck Hagel calls them a 'clear and present danger' The statement came from North Korean army and said it was a warning to the U.S. that it would be 'smashed by... cutting-edge smaller, lighter and diversified nuclear strike means Earlier, U.S. Defense Secretary Chuck Hagel said the secretive state's rhetoric was a growing concern He issued the statement after U.S. stealth bomber were seen patrolling By Daily Mail Reporter and Reuters Reporter The North Korean Army said today it had received final approval to launch 'merciless' nuclear strikes against the United States. The General Staff of the Korean People's Army said it was formally notifying Washington that U.S. threats would be 'smashed by... cutting-edge smaller, lighter and diversified nuclear strike means,' according to a statement published by the official KCNA news agency. The merciless operation of (our) revolutionary armed forces in this regard has been finally examined and ratified. 'The moment of explosion is approaching fast,' the statement read, adding that it could occur 'today or tomorrow.' The pronouncement came just hours after U.S. Defense Secretary Chuck Hagel said North Korea presented a 'clear and present danger' to the U.S. and its allies after days of escalating rhetoric. North Koreans gather for a rally to show their support for a potential nuclear war against the United States. This picture was released by North Korea's official news agency and was not verified by a third party North Koreans hold posters of their previous leaders, Kim Il-sung, left, Kim Jong-Il The poster here reads 'safeguard to the death' as the North Korean army said it had approval to attack the United States with its nuclear weapons Hawaii and Guam would also be outside the range of its medium-range missiles, but U.S. bases in South Korea and Japan may be vulnerable. Hagel issued a statement after U.S. stealth bombers were seen patrolling the border between North and South Korea as part of military exercises which have inflamed tensions in the region. Despite a successful long-range rocket launch in December, it is believed North Korea is years from developing an inter-continental ballistic missile that could strike the mainland United States, AFP reported. This photo of Kim Jon Un and his military advisors was released last week as North Korea announced it was preparing strikes against mainland U.S. This map, built from an EPA photo and a map made by University of Alabama is oriented making the assumption that the leftmost target is Los Angeles and the rightmost target is New York City The North today blocked South Korean workers from entering a jointly run factory zone which is one of the few signs of positive relations between the neighboring countries. U.S. Secretary of State John Kerry yesterday spoke out against North Korea's latest aggressive moves, calling them 'provocative, dangerous and reckless', while Defense Secretary Chuck Hagel said the country was a 'growing threat' to the world's security. March 30: North Korea declared it was entering a 'state of war' against its Southern neighbor. April 3: North Korea announces it had approval to use its nuclear weapons against the United States in a 'merciless' attack North Korea's latest war of words with Seoul and Washington ratcheted up when the United Nations imposed fresh sanctions on the country for its February 12 nuclear test. At the same time, South Korea and the United States have been staging annual war games, which Pyongyang claims are a prelude to an invasion. Those exercises run throughout April. Despite the rhetoric and the cutting of telephone hot lines to the South, Pyongyang has not taken any military action and shows no sign of preparing its 1.2 million strong armed forces for war, Washington says. That would indicate much of the vitriol is intended for domestic consumption to bolster young leader Kim Jong-un ahead of celebrations marking the anniversary of the birthday of Kim Il-sung, the state's founder and the younger Kim's grandfather, on April 15. Kim has also used the rising tensions to cement his grip on power by appointing a key ally of his uncle and aunt as the country's prime minister. 'At least until the end of April, when drills end, the North is likely to keep up the tensions as it had done in previous years,' said Cheong Seong-chang of the Sejong Institute think tank in Seoul. The 30-year old Kim was showing the North could stand up to the United States and to South Korea's new President Park Geun-hye, who took office just a week after the nuclear test, the country's third, said the defector Ahn. 'North Korea doesn't have the economic power that South Korea has but it's stressing its nuclear abilities to show that it can pull equal weight,' he said. North Korean officials said that at the Yongbyon facility a graphite-moderated five-megawatt reactor, which generates spent fuel rods laced with plutonium, would be restarted soon. The reactor is capable of churning out one atomic bomb worth of plutonium - the most common fuel in nuclear weapons - each year.The UN chief says he fears North Korea is on a collision course with other nations that could lead to war. News of the Kaesong closure initially hurt South Korean financial markets. The won currency was trading at a six and a half-month low in early trade but later recovered. He said that any move to re-start operations at the Yongbyon nuclear plant would be 'a direct violation' of North Korea's international commitments and a 'very serious step.'