Australia's trade minister said on Monday China's detention of Rio Tinto employees would not hurt economic relations if handled properly, but said the case was a signal to everyone looking to invest in China.

Simon Crean told reporters Australia wanted more details on the case involving the Rio employees, including its top iron ore salesman in China, Australian Stern Hu, and called for the matter to be handled expeditiously.

It is important for the Chinese government to understand better the concerns we have about the circumstances surrounding not just Mr Hu's detention but the lack of detail, Crean said.

Because this is important as a signal to all people seeking to do business in China.

China is Australia's biggest trade partner, worth $53 billion last year, and iron ore exports injected $14 billion of that, powered by Rio Tinto, Australia's BHP Billiton Ltd and others.

As for its impact on the economic relationship between our two countries, I don't believe -- particularly if this case is handled properly -- it will have any impact on those relations, Crean told reporters ahead of a meeting of Asia-Pacific Economic Cooperation forum trade ministers in Singapore.

Chinese authorities earlier this month arrested four Rio Tinto employees alleging they were involved in stealing state secrets. Rio has defended its employees, saying claims they bribed Chinese steel mills were unfounded.

Crean called on the Chinese authorities to give more details about the case.

We don't know what the charges are because the charges haven't been laid, he said. We have been asking the Chinese government to give us more and better particulars and to do it expeditiously.

He said Hu was in very good health.

Crean underscored the importance of the bilateral trade relationship but also expressed frustration over an apparently stalled free-trade agreement between the two nations.

He said the free trade agreement was progressing but not as fast as he would like.

I believe that the economic relations between the two countries are such that both countries need each other.

The talks are at a stalemate mainly because of China's reluctance to open up to foreign investment and access for agriculture.

I expect the trade will continue to grow between our country as the investment flows will continue to grow. It is far better to understand that and encourage a conducive framework to its development that we conclude the FTA.

We would want to conclude it as soon as we could but it takes two to tango and we await the response of the Chinese.

SURVEY SHOWS SUPPORT FOR RUDD

A survey in Australia on the alleged spy saga has found Australians supported the government's diplomatic efforts to free Hu.

But 58 percent believe Australian Prime Minister Kevin Rudd's knowledge and experience of China will make no difference to how China's government handles the case, an Essential media survey of 1,070 people showed.

Rudd is under pressure at home to personally intervene on behalf of the four China-based staff arrested for harming Beijing's economic interests amid grueling iron ore trade negotiations.

The detentions have complicated annual negotiations on iron ore contract prices between Chinese steel mills and Australia's top mining firms Rio and BHP Billiton. Iron ore is used to make steel.

This year's negotiations have been fraught, since they coincided with the collapse of a deal by Chinese state-owned aluminum firm, Chinalco, to increase its stake in Rio.

(Additional reporting by Neil Chatterjee in Singapore and Rob Taylor in Canberra; Editing by Jeremy Laurence)

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