South Korea is preparing to order all airlines in the country that operate Boeing jets to examine the fuel switches at the centre of an investigation into a deadly Air India crash that killed 260 people.

The Air India airliner carrying 230 passengers and 12 crew members was on its way to the United Kingdom when it crashed into a building shortly after takeoff on June 12, killing all aboard, except for one survivor, and several people on the ground, according to authorities.