President Donald Trump’s blanket 25% tariffs on Mexico and Canada took effect on Tuesday, an extraordinary action aimed at bringing America’s top trading partners to heel. But it threatens to weaken the North American economy,

Growth expectations for the U.S. economy are falling as China and Canada announce their next move in the tit-for-tat trade spat with the White House.

Follow for live updates after President Trump’s tariffs on goods from Canada, Mexico and China went into effect, and for reaction from world leaders, companies and markets.