Sydney  - Giant miner Rio Tinto Ltd has for the first time linked iron ore contract pricing negotiations with its Chinese customers with the detention of Australian citizen Stern Hu.

"At this point in time we're not negotiating," iron ore chief executive Sam Walsh told reporters after a business function in Perth on Friday. "Remember, we have our negotiators detained."

Shanghai-based Hu, the chief of Rio's iron ore business in China, was taken into custody July 5 with three local employees. They have all been accused of industrial espionage intended to strengthen Rio's hand in annual contract negotiations.

Formerly, Rio was careful to dissociate the detentions from the iron-ore price talks.

"We are respecting the judicial system and we're pleased that our four employees have been able to hire top-notch lawyers who will represent them," Walsh said. "We're supporting but standing back from that process and allowing the judicial system to take effect."

While negotiations are stalled, Rio, the world's third largest mining company, is selling to Chinese steel mills at an interim price.

Rio has also been careful not to link the arrests with its decision earlier this year to reject a deal that would have let state-owned Chinalco double its stake in the dual London-Sydney listed company.

China's Chinalco denounced Rio as a "dishonourable woman" who had led China on and then capriciously turned down a 19.5-billion-US-dollar deal in favour of taking up with fellow Anglo-Australian miner BHP Billiton Ltd.

Further inflaming tension in the bilateral relationship has been the visit of Uighur leader Rebiya Kadeer to attend the premiere of an Australian-made documentary about her life and work. (dpa)