President Donald Trump's new 25% tariffs on imports from Mexico and Canada took effect on Tuesday, along with a doubling of duties on Chinese goods to 20%, launching new trade conflicts with the top three U.

Starting just past midnight, imports from Canada and Mexico are now to be taxed at 25%, with Canadian energy products subject to 10% import duties.

Canada, Mexico and China have vowed to retaliate after tariffs on goods entering the US from their countries came into effect.