A robotic submarine has joined the search for Malaysian Airlines flight MH370 for the first time.

The Bluefin-21 drone will be sent down as soon as possible to search for wreckage on the sea floor, explained search chief Angus Houston.

Flight MH370 went missing on March 8th with 239 people on board.

It was flying from Kuala Lumpur to Beijing when it lost contact with air traffic controllers.

A towed pinger locator, which heard signals potentially from the black box recorders on board the plane, has narrowed the search area in the Indian Ocean.

However, no signal has been heard since April 8th, leading experts to speculate the batteries on the recorders may have expired.

An international search has focused on waters west of the Australian city of Perth, with officials are confident they are searching in the right area.