Reuters - Australia's trade minister Simon Birmingham says Australia doesn't know why China's authorities have detained Australia citizen Cheng Lei but he says the risks for Australia's companies doing business with China have changed.

Australia's government confirmed late Monday that Cheng, a business-news anchor on China state TV, had been detained two weeks ago.

"Cheng Lei is an Australian, a journalist who has been working in China for some period of time. I've actually met her and been interviewed by her while overseas myself. I feel for her family very much...and it's why we will do what we can to assist her - as we would and have (done for) any Australian in these sorts of circumstances," Birmingham said on ABC radio

The Australian embassy was given consular access to Cheng via video link Aug. 27, he said. Cheng has two children, both in Australia.

Australia's former ambassador to China, Geoff Raby, a business consultant, said Cheng was a longtime friend and an experienced journalist who had interviewed him many times for her business program.

Business reporting is not usually seen as politically sensitive in China, he said, adding that he was astonished she had been detained.

"She held a degree of skepticism toward some Chinese media, but she was equally strong in arguing China's case if foreign reporting mischaracterized China or was not based on facts," Raby told Reuters.

The Committee to Protect Journalists said in a statement China's authorities should disclose their reasons for holding Cheng or release her.

Steven Butler, CPJ's Asia program coordinator, said: "China - the world's No. 1 jailer of journalists - must make clear whether her detention has anything to do with her media work."

Tensions between Australia and China have been high this year after Australia in April called for an international investigation into the source of the coronavirus pandemic.

China was angered by the move and has since blocked Australian beef imports, placed dumping tariffs on Australian barley and launched an antidumping investigation into wine from Australia. Birmingham told TV network Nine that many of the trade measures lacked substance.

"I've been very concerned at the number of different trade issues that have come our way this year that I think changes the risk profile for Australian businesses in engaging with China," he said.