New York (CNN Business) The trade war President Donald Trump has waged against China could literally turn biblical.

If negotiations between Washington and Beijing falter, Trump has vowed to place tariffs on all of America's imports from China. Book publishers are warning that those tariffs will cause the price of printing the Bible to soar and potentially spark shortages.

The problem is that most US publishers print the Bible in China because of the high cost and complexity involved in printing a text with roughly 800,000 words. HarperCollins Christian Publishing, a leading Bible publisher, estimates that about three-quarters of its Bible manufacturing expenses are in China.

The proposed tariffs amount to "levying a 'Bible Tax' on consumers and religious and educational organizations," HarperCollins Christian Publishing CEO Mark Schoenwald wrote in a letter last month to Trump's top trade official.

The company owns Thomas Nelson and Zondervan, which it said are the two largest Christian book and Bible publishers in the United States. HarperCollins said that the 25% China tariffs would "seriously and disproportionately damage our business and our customers."

HarperCollins has requested that Bibles, testaments, prayer books and other religious s be removed from the list of products facing tariffs. News of the impact from tariffs was previously reported by the Associated Press.

The warning is another reminder of the unintended consequences of the trade war against China, which has already badly hurt American farmers , increased costs for US businesses and slowed the global economy.

"We believe the Administration was unaware of the potential negative impact these proposed tariffs would have on Bibles," Schoenwald said at a hearing in Washington last month.

Apple's AAPL Nike NKE If the next round of tariffs take effect, they would cover everything the United States imports from China, includingiPhones,sneakers, drones, televisions and even L.O.L. Surprise dolls.

Publisher could halt printing of some Bible editions

After meeting with Chinese President Xi Jinping at the G20 summit late last month, Trump announced those tariffs are on hold as the two nations resume negotiations. That trade truce relieved markets and businesses caught in the middle of the tit-for-tat tariff battle.

However, some believe the trade war will re-escalate, due in part to the deep differences between the two nations.

"We still think an across-the-board US tariff on all imports from China is more likely than not," Goldman Sachs chief economist Jan Hatzius wrote in a note to clients on Monday. He said "this is a close call" and likely won't occur until the fall.

If that happens, HarperCollins said it will need to either absorb the cost of the tariffs, or increase prices and reduce sales volume. This would shift an "unfair burden on Bible readers, churches, ministries and outreach organizations," Schoenwald wrote in the June letter to Robert Lighthizer, the United States Trade Representative.

HarperCollins also said that it may need to discontinue certain Bible editions altogether.

"The proposed tariffs on these high-cost but small-margin Bibles would be too much" for the publisher or consumers "to bear," Schoenwald said.

Alternative sources not available

The main obstacle is that Bibles are expensive to print. The high word count — 10 times that of an ordinary book — means that Bibles need to be printed on very thin paper, HarperCollins said. And that thin paper must be printed on special machines.

"Alternative sources for printing are not readily available in the United States or elsewhere," Schoenwald said.

What's more, HarperCollins said rump's tariffs are unlikely to encourage domestic printers to resume investing in this area.

The publisher told CNN Business it has not officially heard from the USTR on its request to have Bibles and other books removed from the tariff list.

When asked by CNN Business, a spokesperson from the USTR referred to Trump's announcement last month at the G20 summit announcing that new tariffs on China are on hold as negotiations resume.

Bible sales in the United States totaled 8.1 million in 2018, according to the NPD, a market research group. That estimate includes all versions of the Bible and variations but not copies that are sold directly by publishers to churches.

That's still twice as much as the 3.5 million copies sold last year of Michelle Obama's "Becoming," the next-best selling book in the United States last year, according to NPD.