Under the deal, Capgemini will be responsible for the delivery of core IT services to BAA’s six airports, managing subcontractors including Computacenter and SITA.

Around 200 of BAA’s IT workers will be eligible for transfer to Capgemini. The fate of the remaining few hundred IT staff has not been specified, though BAA will retain responsibility for "IT strategy, stakeholder management and ensuring the quality of IT services".

This follows a significant reduction in IT staff at BAA in 2009, when it split off Gatwick, Stansted and Glasgow airports, and another in 2008 when it outsourced application management to Logica.

The deal will help to "simplify an unnecessarily complex set of systems" at BAA, it said in a statement, giving clearer visibility into IT costs and allowing it to offer real time information to its airline clients.

It was reported at the end of last year that BAA was weighing up bids from Capgemini and Siemens, which has since sold its IT outsourcing division to Atos Origin.

BAA shared the blame for the IT systems failure that caused a baggage handling pile-up when Heathrow’s Terminal 5 opened in 2008. A parliamentary committee investigating the failure found that causes included poor communication between BAA and airline operator British Airways, insufficient staff training and inadequate systems testing.