Amazon.com Inc. said on Thursday it plans to complete its $13.7 billion acquisition of Whole Foods Market Inc. on Monday after winning antitrust approval from U.S. regulators on Wednesday.

The companies said in a joint statement that Whole Foods will offer lower prices starting on Monday "on a selection of best-selling grocery staples across its stores." Amazon also said that it will start selling Whole Foods brand products on its website.

Amazon said Whole Foods Market will operate as a subsidiary and John Mackey will remain as CEO and Whole Foods Market's headquarters will remain in Austin, Texas

Some grocery store stocks fell after the news. Kroger Co. was down 4.6 percent. Wal-Mart Stores Inc was down 2.1 percent.

Amazon said starting Monday it will cut prices on Whole Trade bananas, organic avocados, organic large brown eggs, organic farmed salmon and tilapia, organic baby kale and baby lettuce, some apples, butter, and other products.

Amazon said its Prime members will eventually become part of Whole Foods Market's customer rewards program.