Why is Iraq 'safe' for BA but not other airlines?

British Airways has said that it will continue to fly over Iraqi airspace, despite several other airlines diverting their planes around the conflict zones.

Emirates Airline, Air France, Virgin Atlantic, Lufthansa and Qantas are among those to have taken avoidance action in order to protect against the threat of Islamic militants on the ground.

But BA chief executive Willie Walsh told the Financial Times: "We fly over Iraq because we consider it safe. If we thought Iraq was unsafe we would not fly over Iraq."

BA has since said it would be reviewing its decision on a daily basis.

Business reporter Theo Leggett explains why airlines have come to differing conclusions.