Thousands of British Airways passengers booked to fly for Christmas have been left grounded by a wave of flight cancellations.
The airline said its operations were hit by a technical issue which has since been resolved.
At least nine long-haul British Airways flights to Heathrow - each due to carry hundreds of passengers - were cancelled across last night and this morning.
Several other flights suffered long delays, including one from the US city of Philadelphia which is expected to land more than five-and-a-half hours behind schedule.
"Our teams have now resolved a temporary issue that affected some of our long-haul flight planning systems overnight, which resulted in delays to our schedule," BA said in a statement.
"We're sorry for the disruption caused to our customers' travel plans," it added.
BA is owned by IAG, which also owns Aer Lingus.
