The man was working in a lift shaft when the accident happened and was pronounced dead at the scene by the emergency services.

Work in the immediate area has been stopped and the Health and Safety Executive have been notified and are now on site. An spokesman for BAA the airport owner said: "Our thoughts are with the worker's family and friends at this very sad time."

It is the second fatality on the £4.4bn project since it started five years ago.

The new terminal is due to open next March.