Mars and General Mills are adding GMO (Genetically Modified Organisms) labeling to all their products nationwide.

And both companies are saying it’s in direct response to a Vermont law requiring all products in the state to have GMO labeling.

Mars says, “In 2014, the state of Vermont passed a mandatory genetically modified (GM) ingredient labeling law that requires most human food products containing GM ingredients to include on-pack labeling as of July 2016. To comply with that law, Mars is introducing clear, on-pack labeling on our products that contain GM ingredients nationwide.”

Meanwhile Jeff Harmening, General Mills executive v.p. and chief operating officer, for U.S. Retail at General Mills, posted a statement on his company’s website late last week calling for “a national solution for GMO labeling.”

“We can’t label our products for only one state without significantly driving up costs for our consumers and we simply will not do that,” Harmening says. “The result: consumers all over the U.S. will soon begin seeing words legislated by the state of Vermont on the labels of many of their favorite General Mills products.”

For its part, Mars already has added the line “Partially produced with genetic engineering” to some bags of M&M’S.

"In terms of timing, we are currently working to amend the labeling of our U.S. products to comply with the Vermont law," a Mars spokesman toldABC News. "Given the size and complexity of our supply chain, GMO-labeled products will appear on store shelves at different times."

However, Mars also says that it believes GMO ingredients are safe.

“We firmly believe GM ingredients are safe,” the company says. “Food developed through biotechnology has been studied extensively and judged safe by a broad range of regulatory agencies, scientists, health professionals, and other experts around the world.”

But the company added that they understand consumers want transparency.

“At Mars, we not only ensure the safety of all raw materials in our products, we’re also committed to being transparent with our consumers so they can understand what’s in the products they love,” the company says.

And General Mills’s Harmening echoed those sentiments.

“All sides of this debate, 20 years of research, and every major health and safety agency in the world agree that GMOs are not a health or safety concern,” he says. “At the same time, we know that some consumers are interested in knowing which products contain GMO ingredients.”