Pyongyang claimed on January 6 that it had successfully tested a hydrogen bomb. The United Nations previously imposed sanctions on North Korea for the three tests it carried out in 2006, 2009 and 2013. The nuclear bomb tested by North Korea in 2013 yielded a 6-9 kiloton blast (equivalent to the detonation of 6-9 tons of dynamite), according to South Korean estimates. For comparison's sake, the bomb that destroyed the Japanese city of Hiroshima in 1945 had a yield of 15 kt. Hydrogen bombs are considerably more powerful; 'Ivy Mike', the first hydrogen bomb ever tested, yielded a 10.4 megaton detonation, 1,000 times that of the bomb North Korea tested in 2013.
The UN is considering a new resolution to impose tighter sanctions on the North. Park, who met with his country's Cabinet on Tuesday, asked officials to step up cooperation with the United States and regional powers to come up with response measures against Pyongyang.