China, the world's top coal importer, brought in 20.78 million tonnes of the fuel last month, data from the General Administration of Customs showed on Sunday. That compares with 25.69 million tonnes in October and 19.15 million tonnes in November last year.
Customs officials at several ports in Guangdong, Jiangsu and Shandong province in eastern China have halted clearance for vessels carrying coal since late October, three traders told Reuters last month.
Traders and utilities also cut back sharply on purchases at the end of last year after signals from Beijing aimed at keeping total imports steady year-on-year.
In the first 11 months of 2019, China imported a total of 299.3 million tonnes of coal, already exceeding 2018's total shipments of 281.2 million tonnes.
Falling profit margins at coal mines in Indonesia, China's second-biggest supplier behind Australia, had also discouraged miners there from selling to China last month, analysts and traders said.
Last week, the state planner issued a statement urging domestic coal miners and power utilities to sign long-term contracts to ensure market supply and stabilise prices.
Benchmark coal prices for 2019 long-term contracts have been set at 535 yuan ($76) a tonne during China's winter coal trade fair this week, unchanged from 2018, two traders told Reuters.
(Reporting by Muyu Xu and Dominique Patton. Editing by Lincoln Feast.)