"A push by North Korea to become a nuclear state cannot be accepted or tolerated," Moon said in an address to the Parliament on Wednesday. "We also will not develop or own [a] nuclear" arsenal.
His statement came as the North recently conducted its sixth – and by far most powerful – nuclear test and carried out several missile tests. The intense development of Pyongyang’s nuclear and missile program has triggered increased security concerns on the Korean Peninsula.
Although Seoul once wanted to obtain nuclear weapons in the 1970s, Washington persuaded the country to give up such plans. The United States stationed tactical nuclear weapons in South Korea until the end of the Cold War in 1991. Some in South Korea have argued that if the US does not agree to return its weapons, Seoul should develop its own nuclear arsenal to restrain Pyongyang’s ambitions.
The 1992 deal stated that Seoul and Pyongyang would not develop nuclear arsenals on the peninsula. Two years later, the US and North Korea reached a denuclearization framework agreement, which, however, collapsed in 2002 and Pyongyang resumed its nuclear program.
The North conducted its first atomic test in 2006 and after Kim Jong-un assumed power in 2011 Pyongyang has been intensely developing its missile and nuclear capabilities. This year has already marked a series of nuclear and missile tests by North Korea, which has resulted in a new spike in tensions over the peninsula and a war of words between Kim and US President Donald Trump.
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Tensions escalated further as Trump warned of "fire and fury" against North Korea and a "calm before the storm," referring to a military solution to the crisis.
Meanwhile, the South Korean president insisted in his address that there could be no US military action in the region without Seoul’s agreement.
"There should be no military action on the peninsula without our prior consent. We will not repeat the tragic history like colonialization and division during which the fate of our nation was determined regardless of our will," Moon said.