Holding the charges of stealing commercial secrets and bribe-taking, four of Rio Tinto's employees in China would be facing a trial in Shanghai court.

They were detained on July 5 in Shanghai, while Rio Tinto Ltd. was acting as lead negotiator for global iron ore suppliers.

However, the trial date hasn't been declared as of now.

"We are very concerned about the nature of these charges", said Sam Walsh, Chief Executive of Rio Tinto's iron ore business.

"The arrests have strained ties between China and Australia, which repeated its call that the case be handled transparently and expeditiously", he added.

As indicated by Rio Tinto, the trial seems to be an outcome of Beijing's endeavor to tighten control over China's dozens of steel producers and consolidate the industry through mergers.

The Shanghai Intermediate Court accepted the case against Australian Stern Hu, manager of Rio's iron ore business in China, and three Chinese nationals.

"One defendant is alleged to have taken bribes worth 70 million Yuan", said Zhai Jian, the lawyer representing Ge Minqiang.

"The loss for some Chinese steel millers is apparently huge", Zhai said further.

Rio has appointed Ian Bauert, a fluent Chinese speaker, to head its operations in China.

Australian Prime Minister Kevin Rudd warned Beijing that the world has an eye at its handling of the case.