British Airways has revealed it is likely to lose £50 million following disruption caused by snow over the festive period.
Releasing its monthly passenger figures earlier, the British flag-carrier said an additional impact was likely to be felt in January from cancelled return journeys.
Overall, traffic - measured in revenue passenger kilometres (RPK) - at the airline fell by 8.3 per cent over December when compared to the previous year.
Passenger capacity - measured in available seat kilometres (ASK) - was down 7.7 per cent on December 2009.
This resulted in a passenger load factor decrease of 0.4 per cent versus last year, to 76.4 per cent, BA added in a statement.
Traffic falls comprised a 1.6 per cent decrease in premium traffic and a 9.6 per cent decrease in non-premium traffic.
Traffic was also affected by bad weather conditions in Europe and North America, causing airport closures and reduced operating capacities.
Cargo - measured in cargo tonne kilometres (CTK) - fell by 10.2 per cent.
British Airways hopes to return to profit during fiscal 2010 following two years of sharp losses.
However, the air was hit by £108 million in losses when flights were grounded by the ash cloud emanating from an Icelandic volcano last year.
A series of – still unresolved - strikes by cabin crew last summer cost it upward of £142 million.
The Unite trade union is presently balloting members of further action.