Beijing: Customs at China's northern port of Dalian has banned imports of Australian coal and will cap overall coal imports from all sources for 2019 at 12 million tonnes, an official at Dalian Port Group has told Reuters.

The indefinite ban on imports from top supplier Australia, effective since the start of February, comes as major ports elsewhere in China prolong clearing times for Australian coal to at least 40 days.

Australia's ties with China have deteriorated since 2017, when Canberra accused China of meddling in its domestic affairs.

Tensions rose again last month after Australia rescinded the visa of a prominent Chinese businessman, just months after barring Chinese telecoms giant Huawei Technologies from supplying equipment to its 5G broadband network.