(Reuters) – Vermont on Thursday (May 8) became the first U.S. state to mandate labeling of foods made with genetically modified organisms as Governor Peter Shumlin signed a law that is widely expected to be challenged in court by some food and agriculture companies. The law, set to take effect July 1, 2016, would for the first time align at least a small part of the United States with more than 60 other countries that require labeling of genetically engineered foods.

And it sets the stage for more than two dozen other states that are currently considering mandatory labeling of such GMO foods. BIO, a trade group whose members include Monsanto Co MON.N, Dow AgroSciences, a unit of Dow Chemical Co DOW.N, and other biotech seed companies said food costs for an average household would rise as $400 per year due to mandatory labeling. BIO and the Grocery Manufacturers Association are backing a proposed federal law that would nullify Vermont’s labeling law and any other mandatory labeling of GMOs in the United States.