(CBS MONEYWATCH) – Publishers of religious books are warning that President Donald Trump’s latest proposed tariffs on Chinese imports could result in a Bible shortage in the U.S.

Tens of millions of bibles are printed in China each year, with some estimates as high as 150 million. Publishers large and small testified against the proposed tariff in hearings last month, saying it would make the Bible more expensive for consumers and Christian organizations that give away Bibles as part of their ministry. The proposed tariffs are currently on hold as trade negotiations resume following months of parrying by U.S. and China officials.

Bibles are printed on “unusually thin paper” that requires specialized machines, Mark Schoenwald, president of HarperCollins Christian Publishing, said in testimony to the U. S. Trade Representative. Up to 75% of what it costs a publisher to make a Bible, with its complex illustrations and ultra-thin pages that make it portable, is spent in China and can’t be handled elsewhere, according to Schoenwald.

The two largest Bible publishers in the United States, Zondervan and Thomas Nelson, are owned by HarperCollins. Together, they command roughly 38% of the American Bible market.

“We believe the administration was unaware of the potential negative impact these proposed tariffs would have on the publishing industry generally, and that it never intended to impose a ‘Bible Tax’ on consumers and religious organizations,” Schoenwald testified.

The full size of the U.S Bible market is difficult to gauge. HarperCollins told the Associated Press it estimates roughly 20 million Bibles are sold in the U.S. each year. The NDP group, which includes NPD BookScan and PubTrack Digital, captured 5.7 million print Bible sales in the U.S. in 2018. But that figure doesn’t capture all sales, including direct sales to congregants.

Still, either of those figures show the Bible is by far the top-selling book in the U.S. The next best-seller behind it in 2018 was Michelle Obama’s “Becoming,” which BookScan estimates sold 3.5 million copies.

The proposed 25% tariff would apply to all books, but critics say it would disproportionately affect Bibles and children’s books. Both tend to have specialized printing requirements that Chinese printers are set up to meet while many domestic printers are not.

“U.S. printers moved their Bible printing facilities abroad decades ago, leaving no substantial domestic manufacturing alternatives,” Schoenwald said.

Some publishers warned that hiking the price of Bibles make them inaccessible to people who earn lower incomes and may even impinge on religious freedom guaranteed in the U.S. Constitution.

“We are extremely concerned that the increased prices would prevent many middle- and low-income Americans from being able to afford Bibles, interfering with the practical ability for them to engage with their faith,” G. Paul Hendrickson, general manager of Hendrickson Publishers, a small firm in Peabody, Massachusetts, testified last month.

Russell Moore, president of the Ethics & Religious Liberty Commission of the Southern Baptist Convention, testified that the proposed tariffs “will impact all Christians’ ability to exercise their religious freedom in the United States.”

Mr. Trump and Chinese President Xi Jinping have hit the pause button on their trade war and agreed to resume discussions that had stalled earlier this year. That means U.S. companies and consumers bracing to pay more for Bibles — as well as to clothing to fireworks — are getting a reprieve on footing the bill for $300 billion in tariffs on Chinese goods threatened by Mr. Trump. For now.

— The Associated Press contributed to this story.

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