Over 160 business groups on Wednesday appealed to U.S. President Donald Trump in a letter to postpone all tariff hikes on Chinese imports scheduled this year, warning that it could hit shoppers with higher prices during the holiday season.

“These tariff rate increases – some starting as early as Sunday – come at the worst possible time, right in the middle of the busy holiday shopping period,” the letter, on behalf of Americans for Free Trade Coalition, said.

“With some products facing tariffs as high as 30 percent, many businesses will have no choice but to pass along those costs to consumers. Price increases will likely hit shoppers just as they are making their holiday purchases.”

The business groups include the National Retail Federation, Retail Industry Leaders Association, Association of Equipment Manufacturers, Consumer Technology Association among others.

The appeal comes as the U.S. Trade Representative’s office earlier on Wednesday reaffirmed President Trump’s plans to impose an additional five-percent tariff on a $300-billion list of Chinese imports starting on September 1 and December 15.

The USTR will impose a 15-percent tariff on some of the targeted goods from September 1, with the rest, including cell phones and laptop computers, to get a 15-percent tariff on December 15, the agency said in a Federal Register notice. The Trump administration had previously planned to impose a 10-percent tariff on these imports.