Rio Tinto says it is surprised and concerned by accusations that four of the miner's staff in China have been involved in bribery.
"Rio Tinto is following developments very closely,'' the world's third-largest mining company said in a statement on Friday.
"The company is surprised and concerned about the allegations.
"As the company has said in earlier statements, we are not aware of any evidence that would support these allegations.''
Rio Tinto's comments followed the release of more details about the allegations made by Chinese authorities against the four staff, which include Australian national Stern Hu.
Australian Foreign Minister Stephen Smith on Friday cited a Chinese government website explaining the allegations against Mr Hu.
"As understood from a Shanghai State Security Bureau, during China's iron ore negotiations with foreign miners in 2009, Stern Hu gathered and stole state secrets from China via illegal means including bribing internal staff of Chinese steel companies,'' Mr Smith said, quoting the website.
"This has caused huge loss to China's national economic security and interests.''
Separately, Reuters has reported the Chinese steel industry official from Beijing-based steelmaker also in detention is being held for revealing China's ''bottom line'' price in its ore negotiations with Rio Tinto. Reuters attributed the information to a ''source,'' without elaborating.
Ready to assist
Rio Tinto said it remained ready to assist Chinese authorities in their investigation involving its four employees.
"Rio Tinto is committed to high standards of business integrity and takes its ethical responsibilities very seriously,'' it said. "Rio Tinto has not been informed by the Chinese authorities of any charges in relation to these allegations.
"We will continue to work to support our employees and their families in China.
"In this regard we have been liaising very closely with the Australian government.''
AAP
