British Airways has cancelled 91 flights due to an IT glitch, while fires near railway lines have caused major disruption for London commuters.

It is believed that 117 flights due to operate to or from Heathrow had been cancelled, while 10 Gatwick flights were also affected.

More than 300 other flights were delayed, with some more than five hours behind schedule.

Around 20,000 passengers will be affected by the cancellations and BA could face a compensation bill in excess of £8 million if all those affected claim what they are entitled to under European Union rules.

The cancellations come as BA passengers posted images on social media that showed long queues of holidaymakers as well as error messages with the BA app.

BA confirmed that they were experiencing a "systems issue" that was affecting check-in and flight departures with Heathrow, Gatwick and London City affected. However, they said this was not a global IT outage.

A BA spokesman said: "We are working as quickly as possible to resolve a systems issue which has resulted in some short-haul cancellations and delays from London airports.

"A number of flights continue to operate but we are advising customers to check ba.com for the latest flight information before coming to the airport.