By Robert Wall and Andrew Tangel
PARIS -- Airbus SE on Monday said it plans to develop its longest-range single-aisle plane yet, adding pressure on rival Boeing Co., which plans a jet for the same market but is distracted by its 737 MAX crisis.
Airbus said the A321XLR, an upgrade to its popular A321neo narrow-body plane, is expected to enter service in 2023, several years before any Boeing midsize plane would be ready. The two planes are aimed at replacing Boeing's out-of-production 757 and some slightly larger 767s.
Boeing's tentative plans call for its jetliner to enter fleets around 2025, though analysts believe the crisis surrounding the grounding of the 737 MAX after two fatal crashes could delay the timing. Boeing has been discussing its concept with airlines, but hasn't confirmed it will build the plane.
Airbus's A321XLR is being designed to fly 4,700 nautical miles and connect cities such as Barcelona and Chicago, where demand typically isn't strong enough to warrant larger, wide-body planes traditionally used on flights between the U.S. and Europe.
"There will be hundreds of these airplanes," Airbus Chief Commercial Officer Christian Scherer said.
Airbus made the announcement at the biennial Paris Air Show, which kicks off Monday and typically is a venue for airlines to place big aircraft orders. Airlines such as JetBlue Airways Corp., British Airways parent International Consolidated Airlines Group SA, and Jetstar, the budget arm of Qantas Airways Ltd., have already signaled strong interest in the new plane even before Airbus gave it the green light.
Air Lease Corp. became the first customer at the Paris Air Show to publicly commit to buying 27 of the planes as part of a 100-aircraft deal that also includes 50 A220-300s. ALC Chief Executive John Plueger said the plane basically performs the same mission that the Boeing aircraft is intended to serve, but is set to do so several years earlier.
Lebanon's Middle East Airlines also placed a firm order for four of the planes.
The plane carries more fuel and Airbus tweaked the wing design to improve performance. The plane would be 30% more efficient than the one it is aimed at replacing.
Boeing has had its eye on the same market for several years. The company has said it is trying to offer a midsize plane with a price tag akin to cheaper single-aisle planes while offering the benefits of more seats typically associated with long-range jets. Boeing has held off on committing to the multibillion-dollar investment as it tries to figure out how to make the numbers work.
Boeing Chief Executive Dennis Muilenburg said Sunday "we're continuing to do our evaluation." The rival Airbus plane, he said, would only "scratch the edge" of the midsize-plane market that the U.S. plane maker estimates has demand for 4,000 to 5,000 jets.
He previously said Boeing would decide this year whether to formally offer the plane to airlines and, if it does, decide next year whether to proceed with development and production.
The launch of the Airbus plane could make it more difficult for Boeing to make the case for spending around $10 billion on a brand-new design, several potential customers said. The Airbus offering "deeply wounds" the case for Boeing's plane, one prospective buyer said.
Delta Air Lines Inc. has to replace about 200 planes in the midsize-plane market in the coming years. Chief Executive Ed Bastian this month said the airline is considering the A321XLR and the Boeing plane, noting that the MAX situation has distracted the U.S. plane maker from pushing ahead with new plane offerings.
Airbus says it can target the same market through a combination of the A321XLR, which will cost far less to develop than a new plane because it merely upgrades an existing aircraft and its A330neo wide-body jet.
For decades, airlines connected U.S. and European cities largely via big hubs. Passengers in smaller cities had to fly to one of those hubs to cross the ocean. But a new generation of budget long-haul airlines, coupled with more efficient single-aisle planes that have the range to cross the Atlantic, have opened direct flights to smaller cities.
Norwegian Air Shuttle ASA, for instance, has used its Boeing 737 narrowbody planes on routes such Providence, R.I., to Dublin. Deutsche Lufthansa AG also has said it would consider the A321XLR for a few trans-Atlantic routes.
Write to Robert Wall at firstname.lastname@example.org and Andrew Tangel at Andrew.Tangel@wsj.com