Retail groups are once again voicing concern about President Donald Trump's latest threat to increase tariffs on $200 billion worth of U.S. imports from China, the most recent chapter in an ongoing saga of simmering trade tensions between the two countries.

The Retail Industry Leaders Association and the National Retail Federation have expressed concern about retaliatory tariffs on their own products and higher costs for consumers. The tariffs would apply to thousands of consumer products, from fish fillets to chandeliers to bicycle tires.

Just as the U.S. and China appeared to be headed toward an agreement on trade, Trump fired off a series of new tweets on May 5 threatening to raise tariffs on imported goods to 25% from the current rate of 10%. He also said that he would "shortly" impose a duty of 25% on $325 billion worth of U.S. imports from China that have so far escaped the tax.

If Trump's threat becomes reality, U.S. producers of exports to China, including farmers, could face new retaliatory tariffs on their sales to buyers in the world's second-largest economy, Hun Quach, the Retail Industry Leaders Association's vice president of international trade, said in a statement on May 6. The trade group represents U.S. retailers ranging from Costco Wholesale Corp. to Walgreens Boots Alliance Inc.

"We want President Trump to successfully reach a deal with China that puts a check on anti-competitive behavior," Quach said. "But a deal that increases tariffs on everyday goods will be a loser for middle class families."

The NRF voiced a similar concern.

"A sudden tariff increase with less than a week’s notice would severely disrupt U.S. businesses, especially small companies that have limited resources to mitigate the impact. If the administration follows through on this threat, American consumers will face higher prices and U.S. jobs will be lost," the organization said in a statement May 5.

Retailers and other consumer-focused companies in the U.S. have been dealing with tariffs on imports from China — as well as China's duties on their own exports to the country — for over a year. Since September, companies have had to offset tariffs implemented under Section 301 of the U.S. Trade Act of 1974, which cover imports from fruit juice to textiles.

Check out some of S&P Global Market Intelligence's extensive coverage of the ongoing trade spat between the U.S. and China:

Stocks plunge amid latest Trump tariff threat on China

Trump: China tariffs to stay in place as enforcement tool in any trade deal

Lawmakers seek tariff exclusion process on $200B of Chinese imports

Consumer imports from China slow after months of stockpiling ahead of tariffs

Consumer, industrial companies plan for tariff increase in FY'19 guidance

Business coalition report: Tariffs cost American companies billions

Furniture, electronics top final US tariff list for $200B of Chinese products

GM scales back on imports of certain auto parts from China, data shows

Furniture retailers expected to raise prices to offset tariffs