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BEIJING, Aug 9 (Reuters) - China's top aluminium foil producers are preparing a legal defence challenging a preliminary U.S. ruling on Wednesday that would impose hefty penalties on imports from the world's top producers, two sources familiar with the matter said.
Loften Aluminum, China's top foil exporter to the United States, is joining 11 other firms to fight the ruling, the first such case since the inauguration of U.S. President Donald Trump, an official at the company said on condition of anonymity.
The China Nonferrous Metals Industry Association (CNIA) is leading the charge on the case, which will be filed with the U.S. International Trade Commission, a CNIA official said.
The companies plan to launch their case this month, the Loften official said. If duties are implemented, Loften would face anti-subsidy duties on its foil sales to the United States of 80.97 percent.
Among the companies involved are Dingsheng Aluminum Group, Xiashun Holdings Ltd and Jiangsu Zhongji Lamination Materials Co Ltd.
The U.S. ruling came five months after the domestic foil industry filed a petition accusing Chinese manufacturers of dumping the product in the United States.
The Chinese challenge will likely heighten tension between the world's two largest economies as Washington threatens further action against China's steel and aluminium sectors.
China produces over half the world's aluminium and exported 1.1 million tonnes of foil last year, up 13 percent from 2015 and more than double levels at the turn of the decade.
(Reporting by Tom Daly and Beijing newsroom; Writing by Josephine Mason; Editing by Dale Hudson and David Evans)