The World Trade Organization's appellate body has largely reversed a previous panel ruling on China-U.S. trade and supports China in its complaint against American anti-dumping measures imposed on four sets of Chinese exports.

China filed its complaint to the WTO in December 2008, requesting that the Dispute Settlement Body establish a panel to probe a U.S. Commerce Department decision to impose anti-dumping and countervailing duties on Chinese-made steel pipe, tubing, sacks and tires and its determinations for the duties.

An appeal was brought to the appellate body in December after China disagreed with part of the rulings made by the panel.

A renewed report from the appellate body not only supported China's claims in specific cases, but also deemed the U.S. approach in forming the anti-dumping duties and countervailing duties inconsistent with WTO agreements.

It outlawed American practices in labeling Chinese state-owned enterprises as "public body" and restricted the U.S. from applying anti-dumping duties to Chinese firms on the basis of an Non-Market Economy methodology.

The practice of "double remedies," which by imposing countervailing duties on the basis of anti-dumping duties repeatedly applies trade measure on Chinese products, was also ruled inconsistent with WTO agreements.

Analysts believe that the appellate body's ruling has a major influence on China's exportation, as some of its trading partners, the U.S. and EU in particular, frequently use anti-dumping and countervailing duties to block Chinese products from entering their markets.

In its Friday announcement, the Chinese Ministry of Commerce welcomed the ruling and hailed it as a monumental victory in promoting fair trade.

China urged the U.S. to immediately adjust its relevant measures on the four sets of Chinese exports, and demanded the U.S. mend its current practices of unfairly overusing trade measures and ensure Chinese companies' rights to fair competition in U.S. markets.

Apart from China's complaints in the case, in recent years, the U.S. has initiated more than 20 other cases of anti-dumping and countervailing investigation, on virtually the same basis and methodology.

The reported is expected to be adopted within 30 days of issuance.