The dispute settlement panel was established in 2023 after a Mexico decree called for a ban on the use of genetically engineered corn in dough and tortillas, and gave instructions to phase out the use of such corn for other food purposes.

But, in a report issued Friday, the panel sided with the US.

It found “that Mexico’s measures are not based on science and undermine the market access that Mexico agreed to provide in the USMCA,” the US trade representative’s office said.

“The panel’s ruling reaffirms the US’ longstanding concerns about Mexico’s biotechnology policies and their detrimental impact on US agricultural exports,” said US trade representative Katherine Tai in a statement.

Agriculture secretary Tom Vilsack added: “This decision ensures that US producers and exporters will continue to have full and fair access to the Mexican market.”

In a joint statement, Mexico’s economy and agriculture ministries expressed disagreement with the panel’s decision but said they would respect the ruling.

“The measures in question are aligned with the principles of protection of public health and the rights of Indigenous peoples,” the statement said.

Under USMCA rules, Mexico has 45 days to comply with the panel’s findings.

The US trade representative’s office noted that the US exported US$4.8 billion of corn to Mexico from January to October this year.

Mexico is the biggest US export market for corn.