President Trump making waves over Canada's milk exports.

FOX's Jon Decker has more from the White House:

President Trump fanning the flames of a trade war with Canada over milk, taking to Twitter to write: "Canada has made business for our dairy farmers in Wisconsin and other border states very difficult. We will not stand for this. Watch!"

Canada maintains a high tariff on imported dairy products. Senate Minority Leader Schumer tweeting, "Glad to see @POTUS join our fight to change Canada's unfair policy that undercuts our farmers."

Canadian officials have blamed global dairy overproduction, not Canadian policies, for the problems of American dairy farmers.

At the White House, Jon Decker, FOX News.