The US, Japan and the European Union have filed a case against China at the World Trade Organization, challenging its restrictions on rare earth exports.
US President Barack Obama accused China of breaking agreed trade rules as he announced the case at the White House.
Beijing has set quotas for exports of rare earths, which are critical to the manufacture of high-tech products from hybrid cars to flat-screen TVs.
It is the first WTO case to be filed jointly by the US, EU and Japan.
They argue that by limiting exports, China, which produces more than 95% of the world’s rare earth metals, has pushed up prices.