The World Trade Organization's dispute settlement panel on Monday supported Japan's claims that a U.S. antidumping law allowing individual firms to seek civil damages violates WTO rules, trade sources said.

The interim report submitted to Japan and the United States follows a final report presented earlier this month supporting a European Union contention that the U.S. Antidumping Act of 1916 violates WTO rules.

The WTO antidumping agreement allows governments to impose duties to protect a domestic industry that has suffered from dumping, or the sale of imported goods at unfairly low prices, after due investigation. But the U.S. law allows individual firms to file dumping suits with local courts, claiming criminal offense as well as civil liability for compensation that could be as high as three times the damage incurred from dumping.