British Airways on Tuesday said it will begin operating a full flight schedule at Heathrow and Gatwick airports on Tuesday after its information technology systems sustained a major failure over a bank holiday weekend starting May 27. The airline apologised for the inconvenience caused, and said it was also prioritising addressing delays in baggage movement.

Analysts have estimated a loss of at least £100 million (approximately Rs 718 crore) in compensation, additional customer care and lost business, The Guardian reported. British Airways Chief Executive Officer Alex Cruz (pictured above) refuted reports that he was resigning over the incident as well as General Union or GMB claims that the failure was a result of the airline’s decision to outsource several IT jobs to India in 2016. “They have all been local issues around a local data center, which has been managed and fixed by local resources,” Cruz told Sky News.

“Once the disruption is over, we will carry out an exhaustive investigation into what caused this incident, and take measures to ensure it never happens again.”

British Airways had said the problem was because of a “power supply issue” and not a cyber attack. Other airlines were not affected. Movement of baggage was frozen after the IT failure, and passenger details were not accessible either. Aviation expert Julian Bray told the BBC, “This is a very serious problem, they should have been able to switch to an alternative system – surely British Airways should be able to do this”.

Customers were asked to check the airline’s website and its Twitter handle for any updates.