Frustrated travellers have taken to Twitter to express their fury, frustration and bemusement at the "catastrophic" British Airways computer system failure that has caused widespread delays — grounding flights from London's Heathrow and Gatwick airports.

A tweet by British Airways confirmed the problem on Saturday (May 27): "We apologise for the current IT systems outage. We are working to resolve the problem as quickly as possible."

But this did little to appease thousands of would-be passengers set to travel over the bank holiday.

As airports struggle to communicate amid the confusion, travellers reported that only passengers within 90 minutes of their departure time will be allowed on to the departures floor at Heathrow.

The incident means passengers are stuck on aircraft waiting to travel, and claim to have been forced to pay for refreshments.

This has also affected travellers abroad looking to travel on British Airways flights.

In the afternoon an announcement at Heathrow Terminal 5 urged passengers to leave the terminal.