Australian Prime Minister Kevin Rudd has warned that China has big economic interests at stake in the case of a mining executive accused of spying.
He said the matter was being watched closely from abroad.
Mr Rudd has been under pressure at home to be more assertive with China, to better protect the detained Australian citizen, Stern Hu.
China says it has evidence of spying, bribery and theft of state secrets in a widening probe of the steel industry.
"Australia of course has significant economic interests in its relationship with China, but I also want to remind our Chinese friends that China too has significant economic interests at stake in its relationship with Australia and with its other commercial partners around the world," Mr Rudd told a press conference.