UPDATE 1-China to extend anti-dumping probe into Australian barley by six months - commerce ministry

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BEIJING, Nov 14 (Reuters) - China's commerce ministry said on Thursday it will extend an anti-dumping investigation into imports of Australian barley by another six months.

The probe, launched a year ago, will be completed by May 19, 2020, said the Ministry of Commerce in a statement on its website.

Seen by many traders as politically motivated, the probe will further damage barley trade between the two countries, which has already suffered from the year-long investigation.

It will also test the political relationship, which has deteriorated in recent years amid allegations that Beijing has committed cyber-attacks and has attempted to interfere in Canberra's domestic affairs.

The ministry's decision comes even after Australian Prime Minister Scott Morrison and Chinese Premier Li Keqiang met earlier this month and promised to try to improve the relationship.

World Trade Organisation rules state anti-dumping probes should be completed within one year, though investigators have an option of an additional six months.

Australia is by far China's top supplier of barley, which is used both in brewing and livestock feed. It exported 6.48 million tonnes in 2017, close to three-quarters of China's imports, and worth about $1.5 billion.

So far this year, however, it has only shipped 2.3 million tonnes to China, or just under half of China's barley purchases. (Reporting by Dominique Patton; Editing by Toby Chopra)