An official who accused Rio Tinto of corporate espionage costing China 700 billion yuan ($A122.36 billion) says he was not close to the case and his "facts" came from state media.
Jiang Ruqin, a former local state secrets bureau director in Jiangsu province, next to Shanghai, in a report published at the weekend repeated claims that Rio stole secrets to gain the upper hand in iron ore price talks.
It also said his actions forced China to pay what it called excessive prices.
He said Rio's alleged actions amounted to "blackmail" costing more than 500 yuan for each of China's 1.3 billion people.
"It also meant that China gave away more than 100 billion dollars, or around 10 percent of Australia's gross domestic product, for free to employers of the commercial spies," he wrote.
The report was written for "China Secrecy On-Line", which is affiliated with the National Administration for Protection of State Secrets.
However, when contacted by AFP on last night, Jiang said he had no special knowledge of the investigation into the activities of Australian citizen Stern Hu and three other Shanghai-based Rio employees arrested on July 5.
"It represented my personal views," he said of the report, speaking from Nanjing, capital of Jiangsu. "I'm not representing any organisation or institution."
The $US100 billion ($A119.96 billion) dollar figure he used was taken from state media, he said.
But the figure appears to be spurious given Australia's entire iron ore exports for the last six years total only $116 billion, according to Australian Bureau of Agricultural and Resource Economics statistics.
The China Youth Daily used the figure in a commentary piece on July 27, estimating that Australian iron ore producers Rio, BHP Biliton and Brazilian mining group Vale had made that amount in excess profits in China since 2004.
The newspaper cited unnamed Chinese steel industry insiders as its source.
Rio shares fell $A2.02, or 3.33 per cent, to $A58.55 on the Australian market yesterday amid fears China was taking its dispute to "a whole new level", Ord Minnett analyst Peter Arden said.
Australian Foreign Minister Stephen Smith played down the report's claims.
"The allegations referred to on the (website) ... are not new," a spokeswoman for Smith said, adding: "The government has always said the Stern Hu case was complex and involved serious allegations."
Rio said last month the espionage accusations were "wholly without foundation."
Jiang's report, which was posted on Saturday, appeared to no longer be accessible when AFP checked. But "China Secrecy On-Line" editors denied it had been removed when contacted by AFP.
The bureau is responsible for protecting the state secrets of China's government and Communist Party organisations and his report sounded authoritative.
"The large amount of data and intelligence on China's steel sector found on Rio Tinto's computers and the huge damage to the economic interests and security of the country are evident," he wrote.
According to Chinese media reports, Rio bribed officials at 16 major Chinese steelmakers during iron ore talks.
Rio and other multinational mining companies allegedly bribed state company executives to get access to information about stock levels, production schedules and volumes, financial information and purchase plans, according to state media reports.