A U.S. trade panel on Wednesday approved heavy anti-dumping duties on South Korean-made washing machines, ending a domestic process initiated by a petition by Whirlpool Corp., a Michigan-based home appliance maker.

The United States International Trade Commission (USITC) announced that it "determined that a U.S. industry is materially injured by reason of imports of certain large residential washers from Korea that the U.S. Department of Commerce has determined are subsidized and from Korea and Mexico that Commerce has determined are sold in the United States at less than fair value."

As a result of the ruling, made unanimously, the department will issue a countervailing duty order on imports of these products from Korea and antidumping duty orders on imports of these products from Korea and Mexico, it added.

LG, Samsung and Daewoo have sold large washers in the U.S. at "dumping margins of 9.29 percent to 82.41 percent," the commission said.

In December, the Department of Commerce set anti-dumping duties for the two leading South Korean makers of electronics products -- LG and Samsung -- at 13.02 percent and 9.29 percent, respectively.

Daewoo was found to be dumping at prices of 82.41 percent, according to the panel.

It also concluded that the firms have also received "countervailable subsidies" of 0.01 percent to 72.30 percent.

The Korean manufacturers are expected to appeal to the World Trade Organization.

"Related measures by the U.S. authorities have been completed," a diplomatic source here said. "It would have some negative impact to exports (by the Korean companies) but it is unlikely to deal a serious blow to price competitiveness of their products or greatly reduce their market share in the U.S."

"It's my understanding that the Korean firms have decided to bring the case to the WTO," added the source. (Yonhap News)