United Airlines is dropping the reservations system it created almost 40 years ago in favor of a platform provided by Hewlett-Packard Co.

Travelport Ltd., the travel services group that now runs the Apollo system used by United, said the carrier planned to terminate their deal March 1, 2012, and transition to the H-P system used by merger partner Continental Airlines.

The move is part of the transition from the merger forming United Continental Holdings Inc., which confirmed the planned switch, and part of a broader shake-up of the business of providing prices, tickets and booking services to the airline and broader travel sectors.

Travelport is embroiled in a battle with American Airlines after the unit of AMR Corp.  this week blocked partner Orbitz Worldwide Inc. from selling its tickets on the company’s U.S. Web sites.

Airlines want to cut costs by renegotiating deals with the global distribution systems such as Apollo and Worldspan — which is also owned by Travelport — that provide booking services to travel agents and consumer-focused Web sites.

Travelport, which revealed the move in a regulatory filing Wednesday, said United’s decision wouldn’t have a financial impact before 2012.

Hewlett-Packard has been expanding its presence in the airline industry against competition from specialist technology providers such as Travelport, Amadeus IT Holdings SA  and Sabre Holdings Corp., which are vying to provide a new reservations system for Southwest Airlines Co.

American last year awarded H-P the contract to provide it with a new booking system.