South Korean nuclear research programs In August 2004 , South Korea revealed the extent of its highly secretive and sensitive nuclear research programs to the IAEA , including some experiments which were conducted without the obligatory reporting to the International Atomic Energy Agency ( IAEA ) called for by South Korea ' s safeguards agreement . The failure to report was reported by the IAEA Secretariat to the IAEA Board of Governors ; however , the IAEA Board of Governors decided to not make a formal finding of noncompliance . South Korea is one of the few countries that has the raw materials and equipment to produce a nuclear weapon but has not . If the South created nuclear weapons it could change the balance of power on the Korean peninsula . The United States has constantly reassured the Republic of Korea that their own nuclear arsenal will suffice in times of danger against North Korea , but recent studies show that over two thirds of South Koreans prefer nuclear weapons to be in their own control , which in time might become a possibility , especially due to the balance of military power changing from the U . S to the ROK in 2015 . Early Nuclear Ambitions . When the United States notified its plan to withdraw USFK in 1970 July , South Korea first considered the possibility of an independent nuclear program . Under the direction of South Korea ' s Weapons Exploitation Committee , the country attempted to obtain plutonium reprocessing facilities following the pullout of the 26 , 000 American soldiers of the 7th Infantry Division in 1971 . After South Vietnam had fallen in April 1975 , then South Korean president , Jung - hee Park first mentioned about its nuclear weapons aspiration during the press conference on 12 June 1975 . However , under pressure from the United States , France eventually decided not to deliver a reprocessing facility to South Korea in 1975 . South Korea ' s nuclear weapons research program effectively ended on April 23 , 1975 with its ratification of the Nuclear Non - Proliferation Treaty . Post - NPT Programs . The South Korean government insists that its nuclear program is for peaceful purposes only . Previously unreported experiments . In 1982 , scientists at the Korean Atomic Energy Research Institute performed an experiment in which they extracted several milligrams of plutonium . Although plutonium has uses other than the manufacture of weapons , the United States later insisted that South Korea not attempt to reprocess plutonium in any way . In exchange , the US agreed to transfer reactor technology and give financial assistance to South Korea ' s nuclear energy program . It was revealed in 2004 that some South Korean scientists continued some studies ; for example , in 1983 and 1984 Korea Atomic Energy Research Institute was conducting chemical experiments related to the handling of spent fuel that crossed the reprocessing boundary . Later , in an experiment at the same facility in 2000 , scientists enriched 200 milligrams of uranium to near - weapons grade ( up to 77 percent ) using laser enrichment . The South Korean government claimed that this research was conducted without its knowledge . While uranium enriched to 77 percent is usually not considered weapons - grade , it could theoretically be used to construct a nuclear weapon . HEU with a purity of 20 % or more is usable in a weapon , but this route is less desirable because far more material is required to obtain critical mass ; thus , the Koreans would have needed to produce much more material to construct a nuclear weapon . This event and the earlier extraction of plutonium went unreported to the IAEA until late 2004 . IAEA Response . Following Seoul ' s disclosure of the above incidents , the IAEA launched a full investigation into South Korea ' s nuclear activities . In a report issued on November 11 , 2004 , the IAEA described the South Korean government ' s failure to report its nuclear activities a matter of ' serious concern ' , but accepted that these experiments never produced more than very small amounts of weaponizeable fissile material . The Board of Governors decided to not make a formal finding of noncompliance , and the matter was not referred to the Security Council . Pierre Goldschmidt , former head of the department of safeguards at the IAEA , has called on the Board of Governors to adopt generic resolutions which would apply to all states in such circumstances and has argued " political considerations played a dominant role in the board ’ s decision " to not make a formal finding of non - compliance . American nuclear weapons in South Korea . In 2013 , South Korean Prime Minister Chung Hong - won rejected calls to again station American tactical nuclear weapons in South Korea . Nuclear Capable state . Although currently South Korea is under the US nuclear umbrella of protection , it could very well break away and try to develop its own nuclear weapons if necessary . Like Japan , South Korea has the raw materials and resources to create nuclear weapons . Although many analysts have not taken a careful and extensive look at previous South Korean experiments , previous incidents show the Republic of Korea ( ROK ) to be able to possess nuclear weapons in anywhere from one to three years if necessary . The ROK has been shown before to create enriched uranium up to 77 % , which although not particularly powerful , shows that South Korea has the potential to make nuclear weapons with higher enriched uranium . South Korea does not have any ICBMs but possesses a wide range of SRBM and MRBMs through the Hyunmoo series of ballistic missiles currently fielded to the ROK Army . The Hyunmoo series of ballistic missiles works similarly to the American Tomahawk Missile , which can be armed with the W80 and W84 nuclear warheads . Theoretically , if needed , the 500 kg conventional warhead could be replaced by a small nuclear warhead . The Hyunmoo missiles can already cover the entire range of North Korea and would drastically change the North ' s disposition if the South had nuclear armed MRBMs . Even though the ROK could procure nukes , currently like Japan it sees no reason to do so with the protection of the American nuclear arsenal . However , if a conflict erupts with the North , South Korea could quickly evolve into a nuclear - armed state and pose even with the North with the support of the US in case a larger country gets involved in the conflict .