American companies of all sizes are on edge over President Donald Trump’s tariffs, but it’s arguably small business that is most exposed. Many smaller firms say they’re having to hike prices, freeze expansion plans or absorb a hit to already-thin profit margins as import bills climb.

The Trump administration has urged Mexico to impose tariffs on Chinese imports as part of ongoing trade negotiations. The pressure comes as the US government threatens to impose 25% tariffs on North American trade partners,