With the Trump administration slapping tariffs on Canadian exports, Canada's government is reminding Arizonans the tariffs will raise consumer prices.

Billboards such as those spotted in the Metro Detroit area this week read, "Tariffs are a tax on your grocery bill."

Ottawa has launched an anti-tariff billboard campaign in 12 mostly Republican-voting states and in Washington, D.C. Although the jury is still out on the campaign's effectiveness, one thing's for certain — it has gone viral.

Canadian Prime Minister Mark Carney told President Donald Trump Wednesday that his nation will retaliate against the United States with tariffs of its own if Trump presses forward with his promised levies – potentially escalating what is already developing into an ugly and damaging trade war.

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

By Promit Mukherjee OTTAWA (Reuters) -Canada plans additional retaliation for U.S. President Donald Trump's auto tariffs and reciprocal tariffs on U.S. trading partners scheduled for early April. Canadian Prime Minister Mark Carney said on Thursday he had not yet determined what actions Canada might take,