Mississippi Republican Sens. Thad Cochran and Roger Wicker are asking the U.S. commerce secretary to uphold a decision reached last summer that determined U.S. catfish producers have been harmed by unfairly-priced frozen fish fillets from Vietnam.

The Commerce Department continues to review an ongoing antidumping action on fillet imports from Vietnam.

Other senators from catfish-producing states who signed the letter to Secretary Penny Pritzker were Sens. Jeff Sessions, R-Ala.; John Boozman, R-Ark.; Mark Pryor, D-Ark.; David Vitter, R-La.; and Mary Landrieu D-La.

“Since 2008, as a direct result of decisions that have been made by your department, imports of frozen fish filets from Vietnam more than tripled. Significant portions of U.S. Production have already been destroyed by the very low prices and large volumes of unfairly traded Vietnamese product.

“Over the past several months, however, your department has issued some decisions which should help accomplish the goal of our antidumping laws — to encourage fair pricing of these Vietnamese imports,” the letter said.

The letter said the department review of markets last year included an evaluation Vietnamese dumping and “many Vietnamese exporters became subject to appropriate antidumping duty deposit rates.”

“We now have some hope for recovery in American catfish production,” the senators said.

The letter also encourages the Commerce Department to resist pressure from the government of Vietnam regarding the antidumping duties applied to its products.

“While our trading relationship with Vietnam is important, the same can be said for our trading relationship with virtually every country whose products are the subjects of U.S. antidumping proceedings. We urge you to insist upon the full, fair and vigorous application of our trade laws, and to appreciate the critical importance to our industry and our states of ensuring fair trade in Vietnamese imports of frozen fish fillets.

“We ask that you ensure that pressure from the Vietnamese Government is not a factor in your Department’s decision-making in this proceeding,” the senators wrote.

The catfish industry has experienced steep declines since 2008. U.S. Department of Agriculture statistics that indicate the market share maintained by U.S. catfish producers dropped from 80 percent to 20 percent since an antidumping case against Vietnam was filed.