Cable from the Chinese Embassy in Pakistan describes different responses of Pakistani government officials and foreign government diplomats in Pakistan regarding China's first nuclear weapons test.

With nuclear proliferation a policy priority for the Jimmy Carter administration, and Pakistan already a special concern, the possibility that China and Pakistan were sharing nuclear weapons-related information began was beginning to worry US government officials. These concerns did not go away during the Reagan administration. While nuclear proliferation was not a top priority, the administration was apprehensive about the implications of the spread of nuclear capabilities and that China may have been aiding and abetting some potential proliferators by selling unsafeguarded nuclear materials.

With nuclear proliferation a policy priority for the Jimmy Carter administration, and Pakistan already a special concern, the possibility that China and Pakistan were sharing nuclear weapons-related information began was beginning to worry US government officials. They had no hard evidence--and the soft evidence that concerned them is massively excised in the December 1979 report just as Beijing and Washington were normalizing relations—so the “precise nature and extent of this cooperation is uncertain.”