The World Trade Organization will examine whether Japan is complying with a ruling against its punitive import charge on South Korean computer chips, an Associated Press report said.
The WTO has twice ruled against a 27.2% charge Tokyo levies on dynamic random access memory made by South Korea's Hynix Semiconductor, the report said.
Earlier this year, the WTO gave Japan until September 1 to bring the tariff in line with international trade rules.
A third ruling against Japan in the dispute could lead to South Korean trade retaliation against Japanese goods or services. The WTO set up a panel to study the matter.
Tokyo said last month it would reduce the tariff on the DRAM chips to 9.1%. South Korea and Hynix, the world's second-largest manufacturer of the DRAMs widely used in personal computers, want the duty scrapped entirely, and have threatened retaliatory measures.
Japan has 'engaged in delaying tactics in order to maintain an illegal countervailing duty on imports from Korea for as long as possible,' South Korea told the WTO's dispute settlement body.
It said Tokyo's decision to lower the tariff still fails to bring it into compliance with WTO rulings.
Japan said it regretted that Korea sought a new WTO investigation, adding that authorities in Tokyo have 'scrupulously' followed WTO recommendations. Japan said 'it stands ready to vigorously defend its position before the panel.'
The US, the European Union and Japan all have imposed duties on the chips because of what they called unfair South Korean government support for Hynix when it nearly collapsed under debt twice this decade.