Trump made demands on Mexico and Canada regarding NAFTA talks. Canada complains Trump is changing the discussion.

Reuters reports Canada, Mexico push back on Trump's 'fair' NAFTA deal suggestion.

The two U.S. trading partners have threatened retaliation unless they are exempted from the planned tariffs, which have rattled financial markets. Both Canada and Mexico send more than 75 percent of their goods exports to the United States.

Canadian Finance Minister Bill Morneau, speaking north of Toronto, said Ottawa is now negotiating NAFTA with a partner that has"changed the terms of the discussion," referring to the United States.

Mexico Must Tackle Drugs

US Crop Subsidies

US Crop Subsidies total $20 billion a year with most of the money ending up in the hands of big, rich farmers producing staple commodities such as corn and soybeans in states such as Iowa.

Corn is the top crop for subsidy payments. The Energy Policy Act of 2005 mandates that billions of gallons of ethanol be blended into vehicle fuel each year, guaranteeing demand, but US corn ethanol subsidies are between $5.5 billion and $7.3 billion per year.