There are almost 18,000 nuclear warheads distributed among nine nuclear-armed states in the world today. Over 90 percent of these are in Russian and U.S. arsenals. But concerns about the growth in nuclear weapons stockpiles are focused on China, India, North Korea and Pakistan.
North Korea is estimated to have four to 10 nuclear warheads — the smallest arsenal of all — and remains the subject of intense diplomatic efforts aimed at reversing its nuclear status. Its nuclear and missile programs are a source of instability and tension in a region vital to global security and economic prosperity.
Having withdrawn from the NPT in 2003, Pyongyang has repeatedly made commitments to abandon the weapons path in return for security assurances and economic assistance, shelved its nuclear ambitions temporarily, and then broken its promises serially.