Mounting trade wars between the United States and its largest economic partners deepened on Tuesday as US tariffs on Canada, Mexico and China kicked in, sparking swift retaliation from Beijing and Ottawa.
Steep US tariffs on Canadian and Mexican goods came into effect as a deadline to avert President Donald Trump's levies passed without the nations striking a deal, in a move set to snarl supply chains.
Trump had unveiled -- and then paused -- blanket tariffs on imports from major trading partners Canada and Mexico in February, accusing them of failing to stop illegal immigration and drug trafficking.
In pushing ahead with the duties, Trump cited a lack of progress in tackling the flow of drugs like fentanyl into the United States.
