China's imports of copper concentrate from Australia plunged for a second month in November to the lowest since at least 2016, customs data showed on Saturday, as a bilateral trade dispute slams China's demand for Australian supply of the commodity.

Arrivals of copper concentrate, or partially processed copper ore, from Australia into China, the world's biggest copper consumer, were 26,717 tonnes last month, according to data released by the General Administration of Customs.

That was down 34% from October and down 77.8% from a year earlier, marking the lowest monthly total in records going back to January 2017.

Australian media reports in early November said the Chinese government had instructed companies not to purchase copper ore and concentrate - as well as at least six other commodities, ranging from coal to lobster - from Australia from Nov. 6 because of souring relations between the two countries.

The November customs data was scheduled for release on Friday but the agency's website was down then.

Copper concentrate, used by smelters to make refined copper, is one of several Australian commodities facing import restrictions in China amid tense relations between the two countries.

Ties soured in 2018 when Australia became the first country to publicly ban China's Huawei Technologies Co from its 5G network, and worsened this year when Australia called for an inquiry into the origins of COVID-19.

Shipments of Australian copper concentrate had fallen more than 50% in October from the previous month, although this was before the reported restrictions were to take effect.

Last month, China's copper concentrate imports from all countries were 1.83 million tonnes, up 8.3% from October but down 15% on year.

Australia accounted for 4.8% of China's total copper concentrate imports in 2019, making it the fifth-biggest supplier, following Chile, Peru, Mongolia and Mexico.