U.S. President Donald Trump will decide on Monday what levels of tariffs he will impose early on Tuesday on Canada and Mexico amid last-minute negotiations over border security and efforts to halt the inflow of fentanyl opioids,

Trudeau, who spent the weekend in London meeting with European leaders, has vowed to retaliate should Trump follow through on his threat of hitting Canada with tariffs. Last month, he announced Canada would hit back by imposing 25 per cent tariffs on $155-billion worth of U.S. goods, but shelved those plans once an agreement to delay was reached.