President Donald Trump's threats to impose punishing tariffs on Canada and Mexico may be part of a strategy to gain leverage ahead of new negotiations on a regional trade agreement, experts said.

Every day a flurry of parts and products are shuttled between Texas and Mexico, part of a cross-border supply chain to make everything from cars and heavy duty machinery to flat screen televisions. The future of that partnership,

President Donald Trump said a 25% tariff on Canada and Mexico could come on February 1 and that a universal tariff isn't off the table.