SIOUX CITY, Iowa (AP) — Seed maker Syngenta is suing a grain elevator operator that has banned the company’s biotech corn. Bunge North America, which operates grain elevators across North America, including one in Council Bluffs, recently posted notices that it would not accept corn planted with Syngenta’s Agrisure Viptera seed. In the lawsuit filed last week in U.S. District Court in Sioux City, St. Louis-based Bunge said the seed has not been approved for export to China.

“We are surprised and disappointed that Syngenta has taken an action which could put at risk a major export market for U.S. corn producers,” St. Louis-based Bunge said in a statement Tuesday. Minnesota-based Syngenta claims Bunge violated federal and state laws and that the seed has been approved for shipment to other international markets, including Australia, Brazil, Japan, Mexico and Korea.

Syngenta spokesman Chuck Lee said only 1 percent of the nation’s corn crop will be exported to China this year. Bunge said it will accept Syngenta’s Agrisure Viptera seed once it is approved by China.

“Until this approval occurs, we must protect the integrity of our export supply chain by not accepting Agrisure Viptera and other varieties that do not have major export market approval,” the company said in its statement. “Our obligation to our farmers is to provide access to the global marketplace and the price benefits of that access. Syngenta’s decision to commercialize Agrisure Viptera should not foreclose our ability to sell to a major market – China,” the company said.

China is currently the seventh largest importer of U.S. corn, according to the U.S. Department of Agriculture.