President Donald Trump has taken executive action to impose or threaten new tariffs on imports from Canada, Mexico and China. The moves fulfill certain campaign promises but also have roiled stock markets and supply chains,

President Donald Trump has taken executive action to impose new tariffs on imports from Canada, China and Mexico

For North American companies, the "wait and see" moment on tariffs is over. U.S. President Donald Trump imposed a 25% levy on goods from Canada and Mexico, along with a 10% tariff on China, in what could be the opening stages of a full-scale trade war likely to create new headaches for executives that have been wrangling with higher costs for several years.