Competition between United Airlines and American Airlines was already fierce at Chicago’s O’Hare International Airport, and now the two airlines seem to be challenging each other with flights to small U.S. destinations as well as major cities.

USA Today reported that American Airlines announced new nonstop service between O’Hare and Appleton, Wisconsin; Birmingham, Alabama; Boise, Idaho; Colorado Springs, Colorado; Greensboro, North Carolina; Greenville, South Carolina; and Ontario, California (summer only). American also recently announced new service between O’Hare and Bozeman, Montana, and Hattiesburg, Mississippi.

United announced a major route expansion in late February 2017 that included new service to Champaign, Illinois; Columbia, Missouri; Rochester, Minnesota; and Santa Rosa, California. The  airline will fly from O’Hare to the three Midwest destinations; United also increased existing service from O’Hare to Charlottesville, Virginia, Reno; Nevada, Spokane, Washington; and Tuscon, Arizona.

“We’re going back on offense,” said United President Scott Kirby in announcing the expansion on 22 routes across the U.S. Interestingly, Kirby left American Airlines last August to become president of United; he has openly questioned why United Airlines allowed American to encroach on its O’Hare routes in the past.

Meanwhile, American Airlines President Robert Isom boasted in a letter to employees, “The greatest strength of our network is our ability to connect small cities with large ones through service to or through our hubs. We’ve added service to many small communities since the (US Airways) merger, providing the traveling public with more options and improving our feed and profitability through our network at the same time.”