Khan, the widely recognized founder of Pakistan's nuclear weapons program, claims in written accounts the weapons-grade uranium was transported to Pakistan from Urumqi, China, The Washington Post reported Friday.
Khan alleges the uranium transfer was part of a secret deal between Mao Zedong, who was president of the Communist Party of China at the time, and then-Pakistani Prime Minister Zulfiqar Ali Bhutto.
Khan alleges the Chinese government also included a blueprint for a previously tested weapon that helped Pakistan in its fledgling efforts to develop nuclear weaponry.
Unidentified U.S. officials said the U.S. government has known about the uranium transfer for decades, the Post said. Those officials allege the Chinese government, once confronted with the claims, denied the transfer occurred.