Consumer group Public Citizen pointed to a 2014 survey showing nine in 10 Americans supported the labeling rules.
Canada and Mexico are readying trade sanctions against the United States after they won a meat labeling dispute on Monday, increasing pressure on the U.S. Congress to scrap the laws.
The World Trade Organization upheld a complaint by Canada and Mexico about U.S. laws requiring retailers to label meat with the country where the animal was born, raised and slaughtered, saying they discriminated against imported livestock.
Republicans, who have a majority in Congress, have signaled they may act to repeal the laws as early as this week, but consumer groups and many Democrats say they provide essential information for shoppers.
Canada has published a hit list of potential U.S. targets, including wine, chocolate, ketchup and cereal.
