Airport operator BAA has reported pre-tax losses of more than £800m for the year ending 31 December 2009.

Compared with the previous year, the Spanish-owned operator of six UK airports saw its pre-tax losses widen by more than 150 per cent as efforts to reduce the group's pension deficits also hit its performance.

BAA offloaded Gatwick Airport to Global Infrastructure Partners in late 2009 after the Competition Commission ordered the sale of three airports - a ruling which has since been appealed. As a result of the sale, BAA was forced to write-down £277.3m as a one-off cost.

Declining passenger numbers have also contributed towards the results, although BAA recorded an 8.3 per cent increase in revenue and a 6.1 per cent increase in net retail income per passenger.

BAA chief executive officer Colin Matthews said: "BAA made substantial progress in 2009, against a difficult economic backdrop. We sold Gatwick airport, returned to the debt capital markets and our future regulation is clearer.

"We expect 2010 to present further economic challenges for the industry as a whole, and we will remain focused on improving our efficiency and the service we offer customers."