The US International Trade Commission said after a six-month review it decided that revoking the existing antidumping duties would likely lead to "continuation or recurrence of material injury within a reasonably foreseeable time."

All six commissioners on the panel voted against lifting the duties.

In January, the ITC found that America's shrimpers were materially injured by imports of some non-canned warmwater shrimp and prawns from Brazil, China, Ecuador, India, Thailand and Vietnam that the Commerce Department said were being sold at less than fair value in the US.

The ITC finding then gave the Commerce Department final approval to impose duties of up to 13.42 percent on shrimp from India and 6.82 percent on shrimp from Thailand.

But the ITC also said at the time that it would collect information on the impact of the Asian tsunami in December which ravaged the industry in India, Thailand and Indonesia and held a "changed circumstances" hearing in April.

At the hearing, US shrimpers, battling images of destruction wrought on the industry by Hurricane Katrina, urged the government not to write them off and not to ease the duties.

Shrimp is the most popular seafood in the United States with every American eating an average of about 4 pounds a year. Around 90 percent of shrimp eaten by US consumers is imported and the total market in 2004 was worth $4.2 billion.