Kroger and Safeway, the two-largest U.S. grocery stores, have promised not to sell salmon that has been genetically modified, Friends of the Earth said.

The grocery stores have joined more than 60 retailers that have made the same commitment, including Target, Trader Joe’s and Whole Foods, according to a March 3 news release from Friends of the Earth, an environmental advocacy group. Retail opposition to the genetically-modified salmon has been increasing in recent years.

AquaBounty Technologies, Inc., based in Waltham, Mass., has been waiting years for approval to sell genetically-engineered salmon. If the company receives the green light from FDA, the fish would become the first genetically-engineered animal approved for human consumption.

"By making commitments to not sell genetically engineered salmon, Kroger and Safeway have joined the large number of grocery chains, from Trader Joe’s to Target, that have wisely chosen to listen to the majority of consumers who do not want to eat genetically engineered fish," said Dana Perls, food and technology policy campaigner with Friends of the Earth, in a statement. “Now Costco, Walmart, Albertsons and other retailers need to catch up and provide their customers with what they want: natural, sustainable seafood that isn’t genetically engineered in a lab."

AquaBounty did not respond to an emailed request for comment.

Although FDA has not approved AquaBounty Technologies' application, the agency made a preliminary finding in 2012 that approval wouldn't "have a significant effect on the quality of the human environment in the United States." The agency also concluded the genetically-engineered fish would be as safe as conventional salmon, affirming a previous finding.