Public interest groups urged the U.S. Department of Justice (DOJ) to block the mega-merger of chemical corporations Dow and DuPont, which the organizations argue is part of a larger effort to put a “corporate cabal” in charge of the nation’s food system.

Dow and DuPont announced in December plans “to merge into a $130 billion giant, thereby establishing the world’s biggest seed and pesticide conglomerate,” as Common Dreams reported.

Food & Water Watch (FWW), National Farmers Union (NFU), and the American Antitrust Institute (AAI) authored the letter (pdf) to the DOJ sent Tuesday.

“The Department of Justice must block this biotechnology mega-merger that would raise farmers’ prices and severely limit the choices for farmers, consumers and rural communities,” said Food & Water Watch executive director Wenonah Hauter in a statement. “Today’s wave of agribusiness and food company mega-mergers is surrendering our food system to a corporate cabal that thwarts our efforts to build an fair and healthy food system.”

Tuesday’s letter argued that the mega-merger “would further consolidate an already highly concentrated biotechnology industry and would likely curtail innovation, raise prices, and reduce cultivation choices for farmers, consumers and the food system.”

The watchdog groups also noted that the “current rumored or announced deals—including Dow-DuPont, ChemChina-Syngenta, and Bayer-Monsanto—would be a third wave of consolidation. Two previous merger waves eliminated the majority of small to medium-sized biotechnology R&D firms to create the Big Six—Monsanto, Syngenta, Bayer, DuPont, Dow and BASF.”