The Biden administration is demanding that Mexican President Andrés Manuel López Obrador scientifically justify his decree that would ban genetically modified corn and the popular herbicide, glyphosate.

The threatened Mexican bans, according to a letter sent by the Office of the U.S. Trade Representative to Mexican Undersecretary of Foreign Trade Alejandro Encinas Najera, “do not appear to be based on a relevant international standard, guideline or recommendation,” so Mexico owes the U.S. an explanation under rules of the U.S.-Mexico-Canada Agreement.

The three-page letter, a copy of which was viewed by Agri-Pulse, asks Mexico for copies of any risk assessments it has completed to support its plans to ban GM corn, and for the scientific evidence it has based its proposal on.

The letter, which was signed by USTR Chief Agricultural Negotiator Doug McKalip and Deputy USTR Jayme White, also demands justifications for Mexico’s rejection of 14 applications of new GM seed traits.

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“Does Mexico consider that any of the fourteen authorization application rejections is based on a relevant international standard, guideline or recommendation?” USTR asks. “If so, please indicate, for each rejection, the manner in which the rejection is based on an identified international standard, guideline or recommendation.”

U.S. lawmakers and the National Corn Growers Association have been pushing for the Biden administration to challenge Mexico over the presidential decree that is scheduled to be implemented in January 2024.

“The letter appears to be the first step prior to requesting technical consultations under USMCA,” says Sharon Bomer Lauritsen, former assistant U.S. Trade Representative for agricultural affairs and commodity policy and founder of AgTrade Strategies LLC.

Technical consultations must be held before a country can request a dispute panel under USMCA.

“We are pleased to see that USTR and USDA are holding Mexico accountable for what it agreed to under USMCA,” NCGA President Tom Haag told Agri-Pulse. “We encourage these officials to hold the line on this issue.” 

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