AIRPORTS operator BAA said it delivered a “robust” financial performance in 2010 – despite disruption caused by volcanic ash, strikes and snow.

The owner of Heathrow and Stansted airports reported a 9% rise in underlying earnings to £966.9m and said losses including one-off items narrowed to £316.6m from the £821.9m recorded a year earlier.

With improved passenger growth at Heathrow over the second half of the year, BAA said it was on course for a strong increase in profitability this year as it looks to deliver additional investment in facilities and further strengthen its finances.

Chief executive Colin Matthews said: “Strong passenger growth at Heathrow in the second half of the year reflected the ongoing improvement in the global economic climate.”

BAA, which was criticised by airlines following disruption to services during December’s snow, said total passenger traffic for Heathrow and Stansted declined by 1.8% to 84.3m due to the one-off factors last year.

At Heathrow, traffic declined by 0.2% to 65.7m – but after adjustments for the exceptional events, the figure is estimated to have increased by up to 3.4%.

Stansted’s reported traffic declined by 7% to 18.6m due to airlines reducing capacity and economic uncertainty, as well as the ash cloud and severe weather.

BAA is facing the sale of Stansted and one of its Scottish airports after it lost a bid to appeal against an order made by the Competition Commission.

It argued that circumstances have changed significantly since the regulator ordered the sell-off, particularly in light of the coalition government’s move to rule out any new runways in the south-east of England.

Gatwick’s £1.5bn sale in December, 2009, which stemmed from the Commission ruling, resulted in a £277m write-down on BAA’s books for 2009, when BAA also took an exceptional charge worth £217.8m relating to its defined benefit pension scheme deficit. The latest results, relating to BAA’s ownership of Heathrow and Stansted, show debt rose by 15.6% to £9.9bn.

BAA, which is owned by Spanish firm Ferrovial, also includes Southampton, Aberdeen, Edinburgh and Glasgow airports.