The trade minister is investigating reports China has suspended lucrative imports of Australian coal.
Chinese steel mills and power plants have reportedly been told to stop using Australian coking and thermal coal.
State-owned ports have apparently been ordered not to offload shipments.
Trade Minister Simon Birmingham confirmed there had been some disruptions to Australian shipments of coal into China, but said there was no evidence to verify a full-blown import ban.
“I have seen the reports and we have certainly been in touch with the Australian industry,” he told ABC radio on Tuesday.
“We have also been working to seek a response from Chinese authorities in relation to the accusations that have been made publicly.”
Senator Birmingham has not been able to contact his Chinese counterpart for many months, with diplomatic relations in the deep freeze.
It is not the first time in recent years Australian coal imports into China have been disrupted.
“There have been patterns of things that look like there are some formal quota systems operating,” the minister said.
“But we take the reports seriously enough to try and seek some assurances from Chinese authorities.”
Minerals Council of Australia chief executive Tania Constable believes informal Chinese quotas might be to blame but remains upbeat about coal exports.
“The trade with China changes through the year based on a range of factors, including quotas,” she told AAP.
“Australia will continue to see demand for its high quality of coal and the medium term outlook remains positive.”
China has launched trade strikes on Australian beef, barley and wine in recent months.
A further strike on Australian coal could smash the economy, which is already deep in recession.
Australia is China’s largest supplier of thermal coal and exports of coking coal surged by 67 per cent in the first half of this year.