President Donald Trump said the U.S. will impose a 35% tariff on all Canadian goods from Aug. 1 and threatened a blanket 15 to 20% levy on most other nations.

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

Wall Street on Friday was poised for a negative open, with stock index futures down, as President Donald Trump slapped a 35% tariff on Canada and warned of further hikes if Ottawa retaliated. S&P 500 futures (SPX) -0.