METALS-Aluminium at lowest since December as dollar gains

* LME/ShFE arb: http://bit.ly/2wZSAEz

* GRAPHIC-2018 asset returns: http://tmsnrt.rs/2jvdmXl (Updates throughout, changes dateline from BEIJING)

LONDON, March 28 (Reuters) - Aluminium prices hit their lowest level in over three months on Wednesday as the dollar firmed and concerns lingered that output cuts in China had not made as big of a dent on supply as expected.

Benchmark aluminium fell 0.2 percent to $2,041 per tonne by 1015 GMT, after earlier touching its lowest since Dec. 14 at $2,033.

The metal used in goods from kitchen utensils to aeroplane parts is down 10 percent so far this year as capacity from top producer China resumes following widespread shutdowns over the winter.

"Throughout that whole period when we supposedly had these capacity cuts, inventories continued to increase so was all production actually being reported or was there some unreported production that was not accounted for," said ING Commodities Strategist Warren Patterson.

"The big question mark was around the quality of Chinese data and we can look again at ShFE inventory numbers."

HEATING SEASON ENDS: China's winter heating season ended on March 15 after Beijing ordered smelters in 28 of its smoggiest northern cities to cut output by 30 percent from mid-November to mid-March. However, the actual volume cut was below expectations, putting pressure on prices.

ALUMINIUM STOCKS: On-warrant LME inventories of aluminium <MALSTX-TOTAL>, those not earmarked for delivery and therefore available to the market, shed 3.4 percent or 35,025 tonnes to 996,500 tonnes.

Meanwhile, ShFE aluminium <AL-STX-SGH> stockpiles held at exchange warehouses touched record highs at 940,318 tonnes, according to exchange data from Friday.

TECHNICALS: Support for aluminium is at the December low of $2,000 and $1,983.5, which is the 50 percent Fibonnaci retracement of the 2017 low to the 2018 high, Marex Spectron said in a note.

TARIFFS: China will soon announce a list of retaliatory tariffs on U.S. exports to China to counter an expected announcement from Washington of proposed new tariffs on Chinese imports, the state-run Global Times said Wednesday.

DOLLAR: Selling of industrial metals was reinforced by a firmer U.S. currency, which when it rises makes dollar-denominated commodities more expensive for holders of other currencies, potentially weighing on demand.

COPPER: Benchmark copper was down 0.3 percent at $6,632 a tonne. Total stocks on the LME rose 4,200 tonnes to 388,175 tonnes.

SPREADS: The rise in copper inventories has seen the discount of LME cash copper to the three-month contract <CMCU0-3> reach $42.50 tonnes, close to January levels touched on Monday of $46. OTHER METALS: Zinc was steady at $3,275.50 per tonne; lead slipped 0.6 percent to $2,392; tin inched down 0.1 percent to $20,850; while nickel was steady at $13,080.

(Additional reporting by Tom Daly; Editing by Susan Fenton)