United Airlines on Tuesday announced an order for 50 long-range Airbus jets, handing another victory from a U.S. airline to Boeing's European rival.

The Chicago-based airline ordered 50 Airbus A321XLR planes to replace its aging Boeing 757-200s, and said that it will start to use the planes for international service in 2024.

The Chicago-based airline plans to fly the jets, single-aisle planes with extra-long range, to Europe from East Coast hubs Newark and Washington, it said in a release.

The carrier is the latest of several U.S. airlines to opt for the planes. JetBlue and American Airlines have both agreed to order some of the long-range single-aisle planes that Airbus is developing.

The decision comes as Boeing is hobbled by the crisis surrounding its 737 Max planes after two crashes, preventing it from dedicating more energy to designing an all-new middle-market plane.

Boeing "currently does not have an aircraft equivalent to the A321XLR to meet our specific operational needs," United's chief commercial officer Andrew Nocella told reporters. He added that United is still open to looking at Boeing's new middle-market airplane but said Airbus' "XLR is a bit smaller aircraft and better suited for these routes."

Fuel-efficiency and increased range are enticing airlines to opt for smaller planes on longer routes as they seek to control their operating costs. United said Tuesday that it is also deferring orders of the larger Airbus A350 planes.