An underwater search vehicle looking for missing flight MH370 has broken down, hampering efforts to locate the jet in the Indian Ocean.

American-made underwater drone, Bluefin-21, stopping working properly only two hours in to its maiden mission.

Fortunately for teams working around the clock to find the Malaysia Airlines jet, spare parts are to be flown out from Britain to get the mission back on course.

But it means yet more delays in finding the missing jet which has been missing since March ???.

Bluefin-21 suffered a "communications problem" during its very first dive and was recalled back to the ADV Ocean Shield, from where it was being controlled. It was damaged again during the recovery, a spokesman said.

Analysis of the vehicle revealed there was a hardware defect in the transponder which prevented the submarine and boat from communicating with each other.

A spokesman for the Joint Agency Coordination Centre, which is leading the search for MH370 said: "Examination of the communications problem has established that a hardware defect exists in the transponder mounted on the Ocean Shield and that a defect may also exist in the transponder mounted on the Bluefin-21.

"This inhibits the ability of the two devices to communicate with each other.

As a consequence, spare parts for both defects will be dispatched from the United Kingdom. The parts are expected to arrive in Western Australia on Sunday."

The crocked sub comes as it emerged that missing MH370 has landed insurer Allianz with an enormous £30m bill. The total insured market loss is expected to be in the region of £350m – including the search for it.