The US has won a World Trade Organization (WTO) ruling against China's use of tariff-rate quotas (TRQ) for rice, wheat and corn. The case, lodged by the Obama administration in late 2016, marks the second U.S. victory in as many months in the country's ongoing trade spat with China. TRQs are two-level tariffs, with limited imports allowed at the lower 'in-quota' tariff and subsequent imports charged an 'out-of-quota' tariff, which is generally much higher. The US argued that the quotas limited market access for its grain exports. Australia, Brazil, India, and the European Union were among those reserving their rights in the dispute brought by the world's largest grain exporter.