Washington CNN  — 

Matt Fass sells American-caught fish, but he’s worried about President Donald Trump’s threatened tariffs on China.

Why? China has become one of the leading fish processors over the past 20 years. That means that fish caught around the world are headed and gutted, frozen, and then shipped to China where it may be deboned or cut into a filet before coming back to the United States.

And that means that it’s on the tariff list. Trump’s tariffs would hit Chinese-processed pollock, salmon and cod – even if it’s originally an American catch – unless the US Trade Representative’s Office decides to exempt those fish from the list.

“We’ve been working with China for 20 to 30 years now. They have the expertise and the infrastructure,” said Fass, president of Maritime Products International.

The Virginia-based fish company imports roughly 20% of the seafood it sells from China, depending on the time of year. Overall, a majority of the fish consumed by Americans is caught or processed overseas.

Fass and a number of other fish importers – including Captain D’s Seafood restaurants and Gorton’s, which you may recognize from the frozen food aisle of your grocery store – are pleading with the Trump administration to keep tariffs off seafood coming from China at a hearing in Washington this week. Facing pressure, the fish were removed from an earlier round of tariffs and several importers expressed frustration Tuesday that they were having the same fight once again.

Alaska Sens. Lisa Murkowski and Dan Sullivan, as well as Rep. Don Young – all Republicans – have also requested that the seafood be removed from the list.

“This unanticipated whiplash is creating tremendous uncertainty for our seafood industry in the months ahead, as they attempt to negotiate sales and contracts with the sudden looming threat of new, unforeseen duties on their products,” they wrote in a letter sent to US Trade Representative Robert Lighthizer.

Business owners don’t know when or if they’ll be hit with a tariff. Trump said last week that there is no deadline for imposing the new taxes, as he continues to negotiate a broad trade deal with Beijing.

“No, I have no deadline. My deadline is what’s up here,” Trump said during a press conference, pointing to his head.

That doesn’t help Fass who recently had to give a customer two prices for salmon and cod – depending on whether the tariff goes into effect. He suspects the restaurant chain will go without putting the seafood on its menu if the tariff goes into effect and the price goes up.

“I don’t want to sound flippant about it, but you almost just have to laugh and say, ‘I don’t know what we’re supposed to do from today to tomorrow,’ ” Fass said.

Some importers told officials on Tuesday that they’d like to move away from processing in China to diversify their supply chain, but the transition could take years. Some species of salmon is processed in the United States, for example, but pink salmon – which is more labor intensive – will have to remain in China in the interim.

“When you think about it, we’re freezing salmon in Alaska, putting it on a barge to Seattle, shipping it to China where it’s reprocessed and sold back to the US consumer. We would love to get away from that. We’d lower our global footprint, everything would be great. But the fact is, we simply cannot compete with those relative labor costs,” said Robert Zuanich, a managing member of Alaska-based Silver Bay Seafoods.

A 25% tariff would likely be passed on to the consumers, and fish sellers say customers will notice it on the lower cost fish. The tariff would hit pollock, which is often made into fish sticks or served as fish and chips or fish sandwiches at restaurants.

George Souza, the president of Endeavor Seafood in Rhode Island, is bracing for higher prices to dampen sales.

“I think a price increase is going to be a fact of life. We certainly don’t make a 25% margin in this industry. We’re blessed in America with an abundance of food, and people might just not go on to eat fish,” Souza said.

The US Trade Representative’s Office will hear from more than 300 importers this week before approving a final tariff list, which could hit goods ranging from shoes to smartphones. If Trump decides to impose the duties, the United States will have tariffs on nearly everything Americans import from China.