PM criticises China over Hu trial

PM Kevin Rudd has voiced concern over China's handling of the Rio Tinto corruption trial, saying a large part of the proceedings left "serious unanswered questions".

Mr Rudd said he had "reservations" about China's move to hold the industrial spying portion of the case behind closed doors, which he described as a lost opportunity to clarify its laws.

Australian businessman Stern Hu was jailed for 10 years on Monday for bribery and commercial espionage surrounding collapsed iron ore negotiations.

Three of his Chinese colleagues received prison terms of between seven and 14 years.

"The trial on the second charge was held in secret with no media and no Australian officials present for it. This has left therefore serious unanswered questions about this conviction," Mr Rudd told reporters.

'Missed opportunity'

"In holding this part of the trial in secret, China I believe has missed an opportunity to demonstrate to the world at large transparency that would be consistent with its emerging global role."

Anglo-Australian Rio, one of the world's top mining companies, moved quickly to sack the four for their "deplorable" behaviour and said it hoped the case would not affect ties with China, its biggest customer.

"Australia condemns bribery wherever it occurs. Australia also, however, has reservations about the manner in which the second charge contained within this court case has been handled," Mr Rudd said.

But he added that Australia's relations with its top trading partner would not be affected by the case, which caused a temporary chilling of ties last year.

Analysts say Rudd, a Mandarin speaker, faces a delicate balance in preserving the vital relationship while not looking too soft on China.

"I believe the bilateral relationship will sustain these sorts of pressures," he said.

"We've had disagreements with our friends in Beijing before, I'm sure we'll have disagreements again."