Manufacturers from Asia, Europe and elsewhere have poured billions into North American supply chains that could be hit by new taxes on Mexico, Canada and China.

US President Donald Trump has said he will follow through with his threat to hit imports from Canada and Mexico with 25% border taxes, known as tariffs, on 1 February. But he added that a decision about whether this would include oil from those countries has not yet been made.

Canada's dollar and Mexico's peso were edging higher on Friday, having dropped Thursday after President Donald Trump signaled he planned to impose tariffs on imports from the two countries. Trump told reporters he would follow through with a plan to impose levies on goods from the U.