The agreement calls for the state-run China National Nuclear Corporation to construct a 1,000-megawatt power plant at Chashma, where two earlier Chinese reactors were built, the American website said.
While there was no confirmation of the news story from Pakistan or China, The Washington Free Beacon quoted unnamed State Department official, who said that such a Chinese move would be in violation of its international promise.
China, which joined NSG in 2005, agreed not to sell additional reactors to Pakistan beyond the two reactors sold earlier.
Under NSG guidelines China is not permitted to sell nuclear goods to any country that is not part of the International Atomic Energy Agency.
“Nuclear Suppliers Group participating governments have discussed the issue of China’s expansion of nuclear cooperation with Pakistan at the last several NSG plenary sessions,” a state department official said.