Serious problems with British Airways' IT systems led to thousands of passengers having their Bank Holiday weekend plans disrupted, after all flights from Heathrow and Gatwick were cancelled on Saturday.

The airline said its terminals at Heathrow and Gatwick became “extremely congested” due to the computer problems. It decided to cancel all flights from both airports before 6pm UK time on Saturday, then extended this to include all the day’s remaining flights from the UK’s largest two airports.

Passengers described "chaotic" scenes at the airports, with some criticising BA for a lack of information.The airline has apologised, and told passengers not to come to the airport. 

The problems affected BA call centres, the website and the mobile app. BA aircraft landing at Heathrow were unable to park as outbound aircraft cannot vacate the gates, which resulted in passengers being stuck on aircraft.

BA chief executive Alex Cruz said: "We believe the root cause was a power supply issue. I am really sorry we our teams were working as hard as they could to resolve these issues."

Mr Cruz did add that there was no evidence the computer problems were the result of a cyber attack.