Australia urged China on Thursday to deal quickly and transparently with the trials of four China-based employees of global miner Rio Tinto accused of bribery and stealing commercial secrets.

We continue to emphasize to the Chinese authorities the need for the case to be handled transparently and expeditiously, a spokesman for Foreign Minister Stephen Smith told Reuters.

China late on Wednesday indicted the four employees, including Australian Stern Hu, Rio Tinto's top iron-ore negotiator at the time of his arrest last year. The move sets the stage for a trial in the case, which has jangled investor nerves.

We are not in a position to say when the trial will commence or the duration of the trial. It is not appropriate to speculate on the outcome or penalties at this time, Smith's spokesman said.

The four are set to stand trial in Shanghai. If found guilty, they could face up to seven years in jail on the commercial secrets charge and up to 20 years on the bribery charge, said Zhang Peihong, a lawyer for one of the accused Chinese nationals.

The indictments will add to investor uncertainty about the power Chinese authorities can wield over business in the world's third-biggest economy.

Top Internet search engine Google became embroiled in a dispute with China last month, criticizing Beijing for censorship and saying it had been the victim of serious hacking from within the country.

The case also poses election-year difficulties for Australian Prime Minister Kevin Rudd, who is a China expert and under pressure from media and political opponents at home to use his relationship with Beijing's leaders to help free Hu.

China is Australia's biggest trade partner. Australia exported $15 billion worth of iron ore to China in 2008, or 41 percent of China's iron ore imports.

DEMANDS FOR OPEN TRIAL

Australian opposition lawmakers and key minor-party senators have pointed to the Rio case as reason for the government to limit Chinese investment in Australian resource firms.

Influential independent Senator Nick Xenophon said Australia must demand an open trial for Hu.

As Australians, we should demand nothing less than a fair and open trial, with standards that are acceptable to us, Xenophon told Reuters.

The fact that there is talk about it being a closed trial that not even members of his family or consulate representatives can attend, that to me is very concerning.

Rudd was expected to comment on the indictments later on Thursday and Canberra has previously warned China that the world is closely watching its handling of the case.

No trial date has been announced, but traditional Chinese New Year holidays beginning this weekend will likely delay the hearing for several weeks.

Rio Tinto was yet to comment on the indictments on Thursday, but has previously said its staff are innocent. The company is due to announce its annual results later on Thursday.

(Reporting by Rob Taylor and James Grubel; Editing by Mark Bendeich)

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