The cancellation of flights by British Airways (BA) following a global IT outage on Saturday caused large queues and congestion at London’s two biggest airports.

The airline said terminals at Heathrow and Gatwick had become extremely congested because of the IT failure and all BA flights scheduled before 1700 GMT had been cancelled.

“Please do not come to the airports. We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide,” said BA, part of Europe’s largest airline group IAG.

It said there was no evidence the problem had been caused by a cyber attack.

The development has disrupted the holiday plans for families with some heading home after waiting at the airport for hours.

Jack Baine was one of many travellers caught in the chaos.

Baine was planning to travel with his wife and two young daughters for a week to Bologna when the outage hit.

He told Reuters that he and his family arrived at 1030 GMT at Heathrow and waited three and half hours in a queue, before eventually being told that flights were cancelled.

His family later headed home, hoping to book a flight on Sunday (May 28).

BA said there was no evidence the problem had been caused by a cyber attack and that terminals at Heathrow and Gatwick had become extremely congested because of the IT failure and all BA flights scheduled before 1700 GMT had been cancelled.