But Sven Schewe, Munich, Germany-based regional director of injection molding machinery for KraussMaffei Technologies GmbH, said the uncertainty is hurting investment in Mexico.
"It is definitely a threat that should be taken seriously," Schewe said. "We have lots of clients in Germany and the United States with plants in Mexico. There is a kind of hesitation about investing in Mexico because of this threat."
Some auto suppliers were making contingency plans for a shutdown. The auto industry relies on both suppliers and assembly plants on both sides of the border.
Magna International Inc., which is headquartered in Aurora, Ontario, but operates 100 facilities in the U.S. and Mexico with more than 57,000 employees, said it is working with customers to accelerate shipments across the border.
Scott Worden, manager of corporate communications for Magna, told Crain's Detroit Business, a sister publication of Plastics News, via email that the “threats and rhetoric around a border closure” have caused the supplier to contingency plan.
Magna shipments were already seeing long delays at border crossings in the first week of April as manufacturers in both countries are rushing to get product over the border, Worden said.
A shutdown would cost the automakers alone $70.2 million in lost production every hour the border is shutdown, according to research from the Center for Automotive Research in Ann Arbor, Mich.
At Plastimagen, some U.S. companies were also arguing against shutting down trade flows.
“I think closing the border would hurt both the U.S. and Mexico,” said Glenn Anderson, senior vice president of sales, marketing and product management for the Advanced Plastics Processing Technologies unit of injection press maker Milacron.
One major U.S.-based compounder said his Mexican customers were asking for additional material in advance of a possible border closing.
But another materials industry executive, Alberto Oba, director of Mexico and Automotive Americas for Kraiburg TPE, said his firm uses two warehouses in Mexico and had no concerns about supply disruptions.
Trump's unusual threats in recent days had prompted statements from many U.S. business groups, including the National Association of Manufacturers and the U.S. Chamber of Commerce.
“A quick look at the numbers reveals that sealing off the southern border could lead to economic consequences even more devastating than a trade war with the Chinese,” the chamber said.
Patty Long, interim president and CEO of the Plastics Industry Association, said in a statement that “even temporary closure” would put plastics jobs at risk and harm the global competitiveness of North America as a region.
“Even more damaging is the uncertainty that such a move would create — disrupting short-term operations and creating doubt for the customers of American companies who need to know that their supply lines won't be impacted by government action,” Long said. “Global competitors would no doubt capitalize on the opportunity to convert our customers to more stable suppliers overseas.”
This story was written by Steve Toloken with reporting at Plastimagen by Plastics News staff reporters Toloken, Bill Bregar and Frank Esposito and Plastics News correspondent Stephen Downer. Dustin Walsh of Crain's Detroit Business contributed to this report.