President Donald Trump late Thursday threatened a 35% tariff on goods imported from Canada, a dramatic escalation in an on-again, off-again trade war with America’s northern neighbor and one of its most important trading partners.

European and US stock markets retreated Friday as US President Donald Trump ramped up his trade war, threatening a higher blanket tariff and a 35-percent levy on Canada.

The Canadian dollar was sliding following President Trump's threat of a 35% tariff against Canada. But the bigger picture is what it might presage for U.S. negotiations with the European Union. The U.