President Trump ordered an additional 25% tariff on Canadian steel and aluminum imports Tuesday in response to Ontario charging Americans in parts of three border states 25% more for electricity.

A fresh wave of tariffs are set to kick in Wednesday, marking the latest escalation in the U.S.-Canada trade war.

The uncertainty around Trump's tariff plans have led to a downturn in the stock market, and the president has not ruled out ...

Yahoo Finance will chronicle the latest news and updates on Trump's tariffs — from the threats to the eventual policy.