U.S. trade officials aren’t satisfied with Mexico’s proposed changes to a presidential decree that would ban genetically modified corn imports by next January.

U.S. Trade Representative (USTR) Chief Agricultural Negotiator Doug McKalip and U.S. Department of Agriculture Under Secretary for Trade and Foreign Agricultural Affairs Alexis Taylor met last week with Mexican government officials to address “grave concerns” with Mexico’s biotechnology policies.

The issue was raised beginning in 2020 when the Mexican...