Arizona Republican Jeff Flake has put a hold on the confirmation of Greg Doud, President Trump’s nominee to be the U.S. Trade Representative’s Chief Agricultural Negotiator. Politico says the hold involves concerns surrounding a controversial produce proposal that the United States has introduced into the North American Free Trade Agreement Negotiations. The seasonal produce proposal is aimed at protecting U.S. farmers from cheaper Mexican imports. Growers in the southeastern U.S. support the proposal. Flake argues that the move would raise the cost of production, reduce the selection of fruits and vegetables for consumers, and hurt growers in western states like Flake’s home-state of Arizona. The largest U.S. port of entry for produce is located in Arizona. Flake hasn’t said what it would take to get him to lift the hold. Flake wrote a letter to U.S. Trade Representative Robert Lighthizer asking him to commit to withdrawing the proposal at the next round of NAFTA talks in Mexico City. Flake wrote, “Efforts that lead to unncessary restrictions on trade with our North American partners will have devastating economic consequences both in Arizona and nationwide.”