Canada faces another set of tariffs in its ongoing trade talks with the U.S. However, in this latest round of tariff announcements, investors have learned to largely tune them out as negotiating bluster rather than policy commitments.

Major stock indexes were slightly lower on Friday as U.S. President Donald Trump's announcement of tariffs on imports from Canada fanned worries about trade tensions, with the Canadian dollar down against the greenback.

The president revived his discredited claims about fentanyl entering the U.S. from Canada to justify his latest proposed rate of 35 percent.