The Office of the U.S. Trade Representative has received Mexico’s responses to U.S. demands for scientific justification of Mexico’s efforts to halt imports of genetically modified corn and the country’s rejection of approval applications for new biotech seed traits, says USTR Chief Agricultural Negotiator Doug McKalip.

USTR is in the process of “translating and analyzing the responses to those questions,” McKalip told reporters Wednesday on the sidelines of a gathering of the National Association of State Departments of Agriculture.

McKalip and Deputy USTR Jayme White sent a letter to Mexican President Andrés Manuel López Obrador’s administration on Jan. 30, demanding the country provide any risk assessments, international standards, guidelines or recommendations that would support its efforts to curtail imports of genetically modified corn from the U.S.

The letter was a direct response to the Mexican presidential decree that was issued in 2020, but Mexico complicated the matter by publishing a revised decree on Monday. That decree specifically bans GM white corn but agrees to allow imports of GM feed corn until Mexico can somehow replace it with non-GM grain sometime in the future.

USTR’s letter demanding the science behind Mexico’s intent to ban GM corn is covered under Chapter 9 of the U.S.-Mexico-Canada Agreement. A country — the U.S. in this case — is allowed to request the scientific reasoning when another country — Mexico — is “constraining, or has the potential to constrain” trade and “the measure is not based on a relevant international standard, guideline, or recommendation.”

The process for disputes laid out in USMCA can be lengthy. The U.S. can call for technical consultations over such a disagreement and the step after that would be dispute consultations. If a resolution cannot be reached, the U.S. can call for a third-party dispute panel, which would act as a judge in the matter.

McKalip also said USTR is analyzing “the totality” of the revised Mexican decree.

Biotechnology Innovation Organization Vice President for Agriculture & Environment Beth Ellikidis told Agri-Pulse the group “applauds USTR for requesting that Mexico provide the justification behind its decree on biotech corn and the rejections of new biotech seed traits as part of its ongoing efforts to ensure Mexico adheres to its USMCA obligations regarding the science-based regulatory review for agricultural biotechnology.”

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