The U.S. will appeal a World Trade Organization (WTO) ruling involving a dispute with Mexico over dolphin-safe tuna labels.

According to a Thomson Reuters report, Mexico has complained for years that the U.S.’s dolphin-safe rules unfairly discriminate against its tuna exports. In 2008, the country challenged those provisions at the WTO.

In September 2011, the WTO ruled that the provisions didn’t discriminate against Mexico, however, they were more restrictive than they needed to be. But the Office of the U.S. Trade Representative disagrees.

“Our dolphin-safe labeling measures for tuna products provide information for American consumers as they make food purchasing decisions for their families,” said Andrea Mead, a spokeswoman for the U.S. Trade Representative.

Mexico’s challenge is centered on one specific U.S. dolphin-safe labeling rule, which says a label cannot be used if a fishing vessel chases and encircles dolphins in order to catch tuna—a practice some Mexican fisherman use.

If the U.S. loses its appeal, it may have to amend its dolphin-safe labeling laws or possibly face Mexican trade sanctions.