SYDNEY: Australia Tuesday said China had rebuffed its latest requests for information on a detained mining executive but insisted it would stay involved in the case for the "long haul."

Foreign Minister Stephen Smith said a third meeting with China's acting ambassador had failed to yield extra information on Rio Tinto's Stern Hu, whose detention has been linked to difficult iron ore negotiations.

"No, and that's why we pressed them both in Canberra and in Beijing," Smith told public broadcaster ABC, when asked if more details were given in Monday's talks.

"But I've made the point in recent days, despite some people thinking that somehow this difficult issue can be magically solved by one phone call, this is a difficult and complex case.

"It requires constant attention, which is what we're giving it. It may well see Australia in this matter for the long haul, and we need to take this step by step, in a detailed, methodical, sensible, rational way."

Smith rejected claims that China had been disrespectful of Australian officials, who were forced to scan government websites and public statements for information about Hu's arrest.

"I've made it crystal-clear as have our officials, that I would have much preferred that this information be given to us through the normal diplomatic channels," Smith said.

"You can be reliably assured that that's a point that has been made in the last 24 hours, to Chinese officials both here and in Beijing."

Treasurer Wayne Swan denied Australia had taken its trade dealings with the world's largest iron ore consumer too lightly, and rejected opposition calls to raise Hu's case at a higher level.

Anglo-Australian mining giant Rio Tinto last month snubbed a massive cash injection from a Chinese state-owned company, and Hu had been leading tough talks on new iron ore contracts.

"I don't think the government has underestimated anything," Swan told reporters.

"We have a consular agreement with them (and) we are dealing with it in a responsible, measured way... these issues are not resolved through megaphone diplomacy."

Hu is accused of espionage and stealing state secrets over the alleged bribery of steel mill officials, a development which analysts say will have sent shudders through the international business community.

His July 5 arrest along with three Chinese colleagues has also created a diplomatic headache for Mandarin-speaking Prime Minister Kevin Rudd, who has made improving relations with Beijing a priority.

"Mr. Rudd's approach seems to be to do nothing, that's not our approach," said opposition leader Malcolm Turnbull.

"I promise you if I was prime minister, I would pick up the phone and I would talk to the president of China and let him know directly the very grave concerns that all Australians have about the detention of Mr. Hu."

China is resource-rich Australia's number two trading partner in a relationship worth 58 billion US dollars last year, according to official figures.

- AFP/yb