numerous reports have emerged of Iranian and North Korean scientists exchanging visits and potentially valuable information. John Bolton, US ambassador to the United Nations from August 2005 to December 2006, wrote on Ap' Tehran and Pyongyang have cooperated on ballistic missiles since at least 1998.

North Korea’s Estimated Stocks of Plutonium and Weapon-Grade Uranium By David Albright and Christina Walrond, Institute for Science and International Security (ISIS), August 16, 2012.The North Korean Plutonium Stock, February 2007 By David Albright and Paul Brannan, Institute for Science and International Security (ISIS), February 20, 2007.Global Trail of Dead Scientists Price of Illicit Pyongyang-Syria Weapons Collaboration.Pyongyang’s Bomb Is Not As Advanced As You May Think, But It Can Get Scarier published by Xu Tianran on Jun 30, 2020.