AP

Representatives from more than 300 companies are scheduled to testify on the Trump administration's proposed China tariffs as part of a week of public hearings.

Many are planning to warn that the 25% tariffs on roughly $300 billion Chinese imports would act as a tax on Americans and threaten jobs at home.

The Trump administration has found support for its calls to address Chinese trade practices seen as unfair. But that backing has waned as the number of products hit by tariffs swells.

As President Donald Trump hurtles toward plans to slap steep tariffs on nearly all imports from China as part of his yearlong trade war, hundreds of businesses are sounding the alarm on what that move would mean for the American economy.

More than 300 companies are scheduled to testify before the Office of the US Trade Representative during a week of public hearings that begin on Monday in Washington. The firms whose high-ranking officials are set to appear include Best Buy, Roku, American Apparel, and Hallmark Cards.

Many are planning to warn that Trump's proposed 25% tariffs on roughly $300 billion worth of Chinese imports would act as a tax on Americans and threaten jobs at home.

"We strongly oppose adding additional tariffs on these and other baby products that parents and caregivers depend on for the safety of their infants," Bradley Mattarocci, the vice president at the childcare-product company Baby Trend, wrote in a testimony summary letter.

"These increased costs will have to be passed on to consumers due to traditionally low-profit margins and their price sensitivity, making these life-saving products unaffordable to much of our country's population," Mattarocci, who was set to appear before the US trade representative Monday morning, added.

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Trump has said the proposed tariffs — which would hit thousands of household products, including electronics and clothing — would be enacted if Chinese President Xi Jinping doesn't meet with him at a multilateral summit in Japan at the end of June.

That would mark the first high-level encounter between the two nations since early May, when nearly a dozen rounds of negotiations stalled after the US said China reneged on key commitments in a draft trade deal. Both countries have since raised tariffs on each other.

The Trump administration has found support for its calls to address Chinese trade practices seen as unfair, such as the forced transfer of foreign technology and large-scale state subsidies. But some have reversed as the number of products hit by tariffs has swelled.

A year ago, the South Carolina company Element Electronics encouraged Trump's protectionist policies. This week, the television maker is expected to testify that broader tariffs would effectively render its facility uncompetitive.

"If the administration were to impose tariffs on LCD panels, Element would be forced to close its South Carolina facility resulting in the loss of all jobs at the facility," David Baer, a counsel for the company who was scheduled to testify Monday afternoon, wrote.

Here's a full list and schedule of the executives scheduled to testify.

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