The United States, the European Union and Japan are filing complaints with the World Trade Organisation against China, over export restrictions on the scarce minerals known as rare earths.
China accounts for more than 95% of the world's supplies of rare earth metals, which are used in a wide variety of products, including the iPhone, flat-screen TVs and electric cars.
Beijing has set quotas for exports of rare earths. The case argues that China, by limiting its exports, has pushed up world prices.
China says the restrictions comply with WTO guidelines and that the quotas were introduced to limit environmental damage caused by excessive mining.
The BBC reports that the minerals are, despite their name, not particulary rare.
They are a collection of 17 elements: scandium, yttrium, and some 15 lanthanides.
