BEIJING, Feb 19 (Reuters) - Shanghai aluminium prices fell on Tuesday, after Malaysia said it would not extend a moratorium on mining bauxite when it expires on March 31, potentially reducing costs in the aluminium supply chain for top producer China. Bauxite is a rock refined to make alumina, which is then used to make aluminium metal. Chinese aluminium prices have been struggling to move away from two-year lows amid weak domestic demand and plentiful supply. "Not only is there a lack of fundamental support for the aluminium market, the cost support from bauxite may start to fade," Helen Lau, an analyst at Argonaut Securities, said in a note, adding that in 2015, before the moratorium, Malaysia accounted for over 40 percent of China's total imports. Australian bauxite prices SMM-BAUX-AUSTA spiked to a near three-year high in January but have since eased. "Recently the increased exports from Guinea and ... Australia have gradually taken the market share away from Malaysia. That said, Malaysia may still be a potential threat ... due to its proximity to China," Lau added. FUNDAMENTALS * SHFE ALUMINIUM: The most traded aluminium contract on the Shanghai Futures Exchange slipped 0.3 percent to 13,405 yuan ($1,978.89) a tonne by the end of the morning. Three-month aluminium on the London Metal Exchange was up 0.1 percent at $1,858 a tonne. * ALUMINIUM: Mining giant Glencore has bought 200,000 tonnes of aluminium on the LME and will take delivery of the metal from warehouses owned by ISTIM UK in Port Klang, Malaysia, five sources familiar with the matter said. * RUSAL: Russia's Rusal is in talks to resume reinsuring its risks with Western companies after Washington lifted sanctions on it, officials with Russian National Reinsurance Co (RNRC) said. * COPPER: Three-month LME copper edged down 0.2 percent to $6,260 a tonne, on course to snap a run of four straight daily gains on optimism over U.S.-China trade talks. ShFE copper was up 1.2 percent, tracking Monday's jump in the LME price, which was also driven by supply concerns. * VEDANTA: India's Supreme Court on Monday set aside an order by an environmental court which had cleared the way for reopening Vedanta's south Indian copper smelter, in a blow to the company's plans to begin operations. * TRADE: Chinese Vice Premier Liu He will visit Washington on Thursday and Friday to continue trade negotiations with the United States, China's Commerce Ministry said.