Abdul Qadeer Khan

Washington, Nov. 13: In 1982, a Pakistani military C-130 left the western Chinese city of Urumqi with a highly unusual cargo: enough weapons-grade uranium for two atomic bombs, according to accounts written by the father of Pakistan’s nuclear weapons program, Abdul Qadeer Khan.

The uranium transfer in five stainless-steel boxes was part of a broad-ranging, secret nuclear deal approved years earlier by Mao Zedong and Prime Minister Zulfiqar Ali Bhutto that culminated in an exceptional, deliberate act of proliferation by a nuclear power, according to the accounts by Khan , and provided to The Washington Post.

US officials say they have known about the transfer for decades and once privately confronted the Chinese — who denied it — but have never raised the issue in public or sought to impose direct sanctions on China for it.

President Obama, who said in April that “the world must stand together to prevent the spread of these weapons”, plans to discuss nuclear proliferation issues while visiting Beijing on Tuesday.

According to Khan, who is under house arrest in Pakistan, the uranium cargo came with a blueprint for a simple weapon that China had already tested, supplying a virtual do-it-yourself kit that significantly speeded Pakistan’s bomb effort. The transfer also started a chain of proliferation.

China’s refusal to acknowledge the transfer and the unwillingness of the US to confront the Chinese publicly demonstrate how difficult it is to counter nuclear proliferation. Although US officials say China is now much more attuned to proliferation dangers, it has demonstrated less enthusiasm than the US for imposing sanctions on Iran over its nuclear efforts, a position Obama wants to discuss.

Although Chinese officials have for a quarter-century denied helping any nation attain a nuclear capability, current and former US officials say Khan’s accounts confirm the US intelligence community’s long-held conclusion that China provided assistance.