China's aluminium imports have hit an annual record high this year with a month to spare, customs data showed on Saturday, as restrictions on power usage by domestic smelters underpin demand for overseas metal.

Arrivals of unwrought aluminium and products - which include primary metal and unwrought, alloyed aluminium - totalled 397,915 tonnes in November, up 34% from 297,043 tonnes in October and up 109.3% year-on-year.

That was the highest monthly total since August 2020 and took imports for the first 11 months of the year to 2.97 million tonnes, beating the previous annual record of 2.7 million tonnes in 2020.

Aluminium hits three-week high on China supply worries

China, the world's top aluminium producer, is a net exporter of the metal but has been importing unprecedented volumes as its rapid recovery from coronavirus outbreaks last year saw Chinese aluminium prices far exceed international prices, opening up a so-called arbitrage for cheaper overseas metal to flow in.

Monthly imports have maintained elevated levels this year as domestic production has been limited by controls on power usage by energy-intensive industries in several Chinese regions.

China's imports of bauxite, the main aluminium ore, were 7.7 million tonnes in November, customs said. That was down 19% from 9.54 million tonnes in October and down 6.6% year-on-year.

January-November bauxite imports were down 5.2% on the year at 98.69 million tonnes.