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.

While much about the threatened tariffs is still unclear, experts predict they would be bad news for all three economies, with few winners.

As U.S. President Donald Trump mulls imposing 25% duties on imports from Canada and Mexico on Feb. 1, focus has shifted to the sectors likely to bear the brunt of the tariffs. About 28%, or about $844 billion,