Over $200 billion in trade is carried by freight rails between U.S., Canada and Mexico, with auto parts, oil, lumber, ag, and chemicals linking the economies.

Canada and Mexico on Friday sought to show U.S. President Donald Trump's administration evidence of progress in curbing the flow of fentanyl opioids into the U.S. ahead of a March 4 deadline for punishing 25% tariffs on their goods imports.

President Trump is threatening tariffs on more than $900 billion worth of goods from Mexico and Canada. Rachel Michelin, president and CEO of the California Retailers Association, said almost every industry would be impacted by the increased tariffs.