Representatives from the U.S. dairy industry say it is “critical” that Congress solve the trade dispute over country-of-origin labeling (COOL) in order to block the progress of damaging new tariffs on dairy exports by Canada and Mexico.

In a letter to the Senate, the National Milk Producers Federation, U.S. Dairy Export Council and International Dairy Foods Association expressed “growing apprehension” that retaliatory tariffs are drawing closer under a finding that said parts of the U.S. country-of-origin labeling (COOL) law violate World Trade Organization (WTO) rules.

The country-of-origin labeling law, or COOL law, would require a label to be placed on meat packages detailing where an animal was born, raised and slaughtered. Consumer groups lobbied for the rule, but Canada and Mexico complained about it to the WTO, which sided with them. Labels were first implemented in 2009 to provide shoppers more information about the origin of their meat. The labels were then updated in 2013.

“(We) urge the Senate to pass legislation to bring the U.S. into compliance with its WTO obligations without further delay,” the groups said, asking the Senate to collaboratively work on an outcome that both Mexico and Canada will agree on.

Last spring, the WTO ruled against the U.S. COOL law. saying that Canada and Mexico could retaliate against U.S. exports in response. American dairy products have been on Canada’s target list for retaliatory tariffs resulting from the ruling.

The full letter can be read here.