UPDATE 1-China to launch anti-dumping investigation into U.S. sorghum imports

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BEIJING, Feb 4 (Reuters) - China will launch an anti-dumping and anti-subsidy investigation into imports of sorghum grown in the United States, the Ministry of Commerce said on Sunday, in a sign of increasing trade tensions between the world's top two economies.

The U.S. is the world's top exporter of the grain and China's largest supplier by far, with imports from the U.S. reaching 4.76 million tonnes in 2017, out of just over 5 million tonnes in total.

The grain is largely used to feed China's huge livestock sector, especially when other grains like corn are more expensive.

But preliminary evidence and information obtained by the commerce ministry found that imported sorghum from the U.S. had been exported at a lower than normal value, it said, damaging local producers.

The ministry said it had initiated the investigation on its own, because the local sector included a large number of small growers who were unable to prepare the necessary documentation.

The investigation of dumping will be carried out for the period from Nov. 1, 2016 until Oct. 31, 2017. Investigation of industrial injury will be from Jan. 1, 2013 until Oct. 31, 2017.

The investigation should be complete by Feb. 4, 2019, it said, but can be extended until Aug. 4, 2019.

The trade action comes a year after Beijing slapped hefty anti-dumping and anti-subsidy duties on imports of distillers dried grains (DDGS) from the U.S., another product used as a feed ingredient, although it recently reduced VAT on DDGS imports. (Reporting by Dominique Patton)