North Korea which is formally known as DPRK or Democratic People’s Republic of Korea has an active and sophisticated and advanced ballistic missile programs and nuclear weapons. Not only that, they’re believed as well to have biological and chemical weapon capabilities.
North Korea has ambitious nuclear programs dating back to Korean War in the 50s. However, it came to the attention of international community in 92’. This is when the IAEA or International Atomic Energy Agency has discovered that its nuclear activities were deeper than what it initially declared. With these revelations, it led North Korea to withdraw itself from IAEA after couple of years.
As a way of preventing North Korea to withdraw from NPT, US and North Korea has negotiated to an Agreed Framework wherein, Pyongyang will freeze their nuclear activities and give accessibility to inspectors of the IAEA.
This is in exchange of the supplied light water reactors as well as energy assistance from United States.
However, North Korea made a decision to withdraw itself from NPT in January of 2003 which prompts Japan, South Korea, Russia, China and US to reach to a diplomatic solution. However, after 6 years, the talks fail and no diplomatic initiatives were successful in denuclearizing North Korea until 2018.