The trial of four Rio Tinto staff charged with commercial spying in China will begin on 22 March in a Shanghai court, Australia's foreign affairs department said on Wednesday.

The four employees of the Anglo-Australian miner, including Australian citizen Stern Hu, have been in Chinese custody since July over accusations of illegally obtaining commercial secrets.
 

The case has caused tensions between Australia and China and placed a cloud over already contentious iron ore price negotiations between China and Rio, its fellow Australian firm BHP Billiton and Brazil's Vale.
 

The latest news did not hit Rio's shares, which rose 1.25 percent in London, outpacing the FTSE and rival BHP.
 

The stock has risen nearly 22 percent since early February on hopes that miners can win record price hikes in iron ore talks with steelmakers in China and Japan.
 

"Mr Hu and the other defendants will be tried by the Shanghai No. 1 Intermediate People's Court, commencing on Monday 22 March," said Australia's foreign affairs department, after being advised of the trial date by court officials.
 

The trial will be open to hear bribery charges, but will then be closed to deal with infringement of commercial secrets charges, the department said in a statement.
 

"Australian officials have asked for this to be reconsidered. We are pleased that this case is now moving to trial," it said.
 

Hu was formally arrested on 11 August with three Chinese Rio executives, testing China's relations with major resource trade partner Australia.

Close ties
China is Australia's biggest trade partner, with trade worth $53 billion last year. Australia exported $15 billion worth of iron ore to China in 2008, or 41 percent of China's iron ore imports.
 

Rio in February named a fluent Mandarin speaker, Ian Bauert, to head its China business. Bauert, a 30 year Rio Tinto veteran who opened the company's first China office 25 years ago, is specifically charged with improving rocky relations with the Australian miner's largest customer.
 

Rio was not immediately available for comment on the trial. A lawyer for Rio employee Ge Minqiang confirmed the trial date, but said he did not know how long the trial would last.
 

"Its not up to my client to say whether he's guilty or not. He can only testify to the facts. It's up to the court to say if he's guilty or not," said Zhai Jian.
 

Tao Wuping, lawyer for co-accused Liu Caikui, said he had not received the court notification.
 

Asked how his client would plead, Tao said: "I'm not going to go into all that. Wait for the trial".
 

Influential Australian independent Senator Nick Xenophon urged China to ensure the trial of Hu and the other Rio employees be fair and open. "The eyes of the world are on this trial," he told Reuters in Canberra.
 

Source: Reuters